Remove Widevine ARM64 DLL fix

browser/net/brave_static_redirect_network_delegate_helper.cc

@@ -15,7 +15,6 @@
 #include "brave/browser/net/brave_geolocation_buildflags.h"
 #include "brave/browser/safebrowsing/buildflags.h"
 #include "brave/components/constants/network_constants.h"
-#include "brave/components/widevine/static_buildflags.h"
 #include "extensions/common/url_pattern.h"
 #include "net/base/net_errors.h"
 
@@ -88,10 +87,6 @@ int OnBeforeURLRequest_StaticRedirectWorkForGURL(
   static base::NoDestructor<URLPattern> widevine_google_dl_pattern(
       URLPattern::SCHEME_HTTP | URLPattern::SCHEME_HTTPS,
       kWidevineGoogleDlPrefix);
-#if BUILDFLAG(WIDEVINE_ARM64_DLL_FIX)
-  static base::NoDestructor<URLPattern> widevine_google_dl_pattern_win_arm64(
-      URLPattern::SCHEME_HTTPS, kWidevineGoogleDlPrefixWinArm64);
-#endif  // BUILDFLAG(WIDEVINE_ARM64_DLL_FIX)
 
   if (geo_pattern->MatchesURL(request_url)) {
     *new_url = GURL(BUILDFLAG(GOOGLEAPIS_URL));
@@ -170,9 +165,6 @@ int OnBeforeURLRequest_StaticRedirectWorkForGURL(
   }
 
   if (googleDl_pattern->MatchesURL(request_url) &&
-#if BUILDFLAG(WIDEVINE_ARM64_DLL_FIX)
-      !widevine_google_dl_pattern_win_arm64->MatchesURL(request_url) &&
-#endif
       !widevine_google_dl_pattern->MatchesURL(request_url)) {
     replacements.SetSchemeStr("https");
     replacements.SetHostStr(kBraveRedirectorProxy);

browser/net/sources.gni

@@ -81,7 +81,6 @@ brave_browser_net_deps = [
   "//brave/components/localhost_permission",
   "//brave/components/query_filter",
   "//brave/components/update_client:buildflags",
-  "//brave/components/widevine:static_buildflags",
   "//brave/extensions:common",
   "//chrome/browser:browser_process",
   "//chrome/browser/profiles",

browser/widevine/README.md

@@ -28,77 +28,3 @@ with a redirect to Google's server in this case. This works as long as a single
 update check request only polls for Widevine, and not also for any other
 components. We have a special class, `SequentialUpdateChecker`, that makes sure
 that this is the case.
-
-### Widevine in Arm64 Brave on Windows: WIDEVINE_ARM64_DLL_FIX
-
-As of this writing, Google does not offer Arm64 binaries for Widevine on
-Windows. When Arm64 Brave polls Google's component update server for Widevine,
-then it receives a "noupdate" response, meaning that no version could be found.
-In effect, out of the box, Widevine cannot be installed in Arm64 Brave on
-Windows.
-
-However, there is a workaround: When we poll for an x64 version of the
-component, then we get the necessary base files, plus some x64-specific
-binaries. The remaining necessary binaries for Arm64 are available in a Zip file
-on Google's servers. By placing them into the
-`WidevineCdm\<version>\_platform_specific\win_arm64` directory of the component,
-we can obtain a copy of Widevine that works in Arm64 Brave on Windows.
-
-Brave's `WIDEVINE_ARM64_DLL_FIX` implements the above workaround in code. When
-an update check for Widevine returns "noupdate", then the workaround repeats the
-update check, pretending to be from the `x64` architecture. It installs the x64
-version of the component and then additionally downloads the Arm64 zip file from
-Google's server. This gives us a working copy of Widevine in Arm64 Brave.
-
-The facts that upstream can be compiled for Arm64 on Windows and that Google
-publicly serves Arm64 binaries of Widevine make it seem likely that a native
-Widevine component for this architecture will also be available in the future.
-For this reason, our workaround is guarded by a build flag. Once the workaround
-is no longer required, the build flag makes it very easy to clean up the
-associated code.
-
-**Further details about the present implementation of WIDEVINE_ARM64_DLL_FIX:**
-
-The details below were compiled at the time of the initial implementation, to
-simplify the associated code review. They may be wholly or partially out of
-date by the time you read this.
-
-The first entry point into the implementation is in `update_checker.cc`, in
-`SequentialUpdateChecker::UpdateResultAvailable`. It handles the symptom of the
-current limitation: The browser asks the component update server "Do you have
-the Widevine component?", implicitly sending its architecture, which is Arm64.
-The server responds `"noupdate"`, which means there is no such version. When
-this happens, `UpdateResultAvailable` repeats the update check with a fake
-`x64` architecture.
-
-There is some additional code in `UpdateResultAvailable` that handles the case
-when the server responds `noupdate` not because there is no Arm64 version of
-Widevine at all, but because there is just no _new_ version. If we ever receive
-an Arm64 version of Widevine from the update server, then we disable our
-workaround to not fall back to `x64`. This information is persisted via
-`SequentialUpdateChecker::SetPersistedFlag` and `...:GetPersistedFlag`.
-
-The fake architecture is passed from `update_checker.cc` to
-`protocol_serializer.cc` via the `additional_attributes` parameter of
-`MakeProtocolRequest`.
-
-When the browser receives the response from the update server, it installs the
-Widevine component. Upstream has some custom logic for this in
-`widevine_cdm_component_installer.cc`. We extend this logic to in particular
-overwrite `WidevineCdmComponentInstallerPolicy::OnCustomInstall`. This gets
-called by upstream when the "normal" installation of the component is complete.
-Our additional code downloads and unpacks the external zip file with the
-necessary Arm64 binaries. It also applies some patches to make upstream accept
-the foreign implementation.
-
-To be able to download the Arm64 binaries, the `OnCustomInstall` method
-mentioned above needs a `SharedURLLoaderFactory`. Several sections of our code
-make sure that it receives such an instance in our and upstream's calls of
-`RegisterWidevineCdmComponent`.
-
-Brave intercepts network requests to certain domains for privacy reasons. One
-such domain is `dl.google.com`, which Brave redirects to `redirector.brave.com`.
-Our attempt to download the Zip file with additional Arm64 binaries would
-normally be prevented by this mechanism. We add an exception to
-`brave_static_redirect_network_delegate_helper.cc` so that the Zip file can in
-fact be downloaded.

browser/widevine/widevine_utils.cc

@@ -10,7 +10,6 @@
 #include "brave/browser/widevine/widevine_permission_request.h"
 #include "brave/components/constants/pref_names.h"
 #include "brave/components/widevine/constants.h"
-#include "brave/components/widevine/static_buildflags.h"
 #include "brave/grit/brave_generated_resources.h"
 #include "build/build_config.h"
 #include "chrome/browser/browser_process.h"
@@ -41,9 +40,6 @@ void EnableWidevineCdm() {
   SetWidevineEnabled(true);
 #if BUILDFLAG(ENABLE_WIDEVINE_CDM_COMPONENT)
   RegisterWidevineCdmComponent(g_browser_process->component_updater(),
-#if BUILDFLAG(WIDEVINE_ARM64_DLL_FIX)
-                               g_browser_process->shared_url_loader_factory(),
-#endif
                                base::BindOnce(&InstallWidevineOnceRegistered));
 #endif
 }

chromium_src/base/threading/thread_restrictions.h

@@ -6,8 +6,6 @@
 #ifndef BRAVE_CHROMIUM_SRC_BASE_THREADING_THREAD_RESTRICTIONS_H_
 #define BRAVE_CHROMIUM_SRC_BASE_THREADING_THREAD_RESTRICTIONS_H_
 
-#include "brave/components/widevine/static_buildflags.h"
-
 class BraveBrowsingDataRemoverDelegate;
 namespace ipfs {
 class IpfsService;
@@ -16,32 +14,13 @@ namespace brave {
 class ProcessLauncher;
 }
 
-#if BUILDFLAG(WIDEVINE_ARM64_DLL_FIX)
-namespace component_updater {
-class WidevineArm64DllInstaller;
-}
-#endif
-
-#define BRAVE_SCOPED_ALLOW_BASE_SYNC_PRIMITIVES_H_BASE \
-  friend class ::BraveBrowsingDataRemoverDelegate;     \
-  friend class ipfs::IpfsService;                      \
+#define BRAVE_SCOPED_ALLOW_BASE_SYNC_PRIMITIVES_H  \
+  friend class ::BraveBrowsingDataRemoverDelegate; \
+  friend class ipfs::IpfsService;                  \
   friend class brave::ProcessLauncher;
 
-#if BUILDFLAG(WIDEVINE_ARM64_DLL_FIX)
-// WidevineArm64DllInstaller needs to use TimedWait:
-#define BRAVE_SCOPED_ALLOW_BASE_SYNC_PRIMITIVES_WIDEVINE_ARM64_DLL_FIX \
-  friend class component_updater::WidevineArm64DllInstaller;
-#else
-#define BRAVE_SCOPED_ALLOW_BASE_SYNC_PRIMITIVES_WIDEVINE_ARM64_DLL_FIX
-#endif
-
-#define BRAVE_SCOPED_ALLOW_BASE_SYNC_PRIMITIVES_H \
-  BRAVE_SCOPED_ALLOW_BASE_SYNC_PRIMITIVES_H_BASE  \
-  BRAVE_SCOPED_ALLOW_BASE_SYNC_PRIMITIVES_WIDEVINE_ARM64_DLL_FIX
-
 #include "src/base/threading/thread_restrictions.h"  // IWYU pragma: export
+
 #undef BRAVE_SCOPED_ALLOW_BASE_SYNC_PRIMITIVES_H
-#undef BRAVE_SCOPED_ALLOW_BASE_SYNC_PRIMITIVES_H_BASE
-#undef BRAVE_SCOPED_ALLOW_BASE_SYNC_PRIMITIVES_WIDEVINE_ARM64_DLL_FIX
 
 #endif  // BRAVE_CHROMIUM_SRC_BASE_THREADING_THREAD_RESTRICTIONS_H_

chromium_src/check_chromium_src_config.json5

@@ -40,7 +40,6 @@
         "components/privacy_sandbox/privacy_sandbox_settings_unittest.cc",
         "components/search_engines/brave_template_url_prepopulate_data_unittest.cc",
         "components/search_engines/brave_template_url_service_util_unittest.cc",
-        "components/update_client/brave_persisted_data_unittest.cc",
         "components/variations/service/field_trial_unittest.cc",
         "net/base/brave_proxy_string_util_unittest.cc",
         "net/cookies/brave_canonical_cookie_unittest.cc",

chromium_src/chrome/browser/component_updater/registration.cc

@@ -5,22 +5,11 @@
 
 #include "chrome/browser/component_updater/registration.h"
 #include "base/functional/bind.h"
-#include "brave/components/widevine/static_buildflags.h"
-#include "chrome/browser/component_updater/widevine_cdm_component_installer.h"
 
 #define RegisterComponentsForUpdate RegisterComponentsForUpdate_ChromiumImpl
 
-#if BUILDFLAG(WIDEVINE_ARM64_DLL_FIX)
-#define RegisterWidevineCdmComponent(cus) \
-  RegisterWidevineCdmComponent(cus,       \
-                               g_browser_process->shared_url_loader_factory())
-#else
-#define RegisterWidevineCdmComponent(cus) RegisterWidevineCdmComponent(cus)
-#endif
-
 #include "src/chrome/browser/component_updater/registration.cc"
 
-#undef RegisterWidevineCdmComponent
 #undef RegisterComponentsForUpdate
 
 #include "brave/components/brave_wallet/browser/wallet_data_files_installer.h"