Merge pull request mozilla#10869 from Rob--W/issue-10645-preserve-htt…

…p-referer-again

Restore referrer preserving functionality in Chrome 72+

extensions/chromium/preserve-referer.js

@@ -41,14 +41,26 @@ var g_requestHeaders = {};
 // g_referrers[tabId][frameId] = referrer of PDF frame.
 var g_referrers = {};
 
+var extraInfoSpecWithHeaders; // = ['requestHeaders', 'extraHeaders']
+
 (function() {
   var requestFilter = {
     urls: ['*://*/*'],
     types: ['main_frame', 'sub_frame'],
   };
-  chrome.webRequest.onSendHeaders.addListener(function(details) {
-    g_requestHeaders[details.requestId] = details.requestHeaders;
-  }, requestFilter, ['requestHeaders']);
+  function registerListener(extraInfoSpec) {
+    extraInfoSpecWithHeaders = extraInfoSpec;
+    // May throw if the given extraInfoSpec is unsupported.
+    chrome.webRequest.onSendHeaders.addListener(function(details) {
+      g_requestHeaders[details.requestId] = details.requestHeaders;
+    }, requestFilter, extraInfoSpec);
+  }
+  try {
+    registerListener(['requestHeaders', 'extraHeaders']);
+  } catch (e) {
+    // "extraHeaders" is not supported in Chrome 71 and earlier.
+    registerListener(['requestHeaders']);
+  }
   chrome.webRequest.onBeforeRedirect.addListener(forgetHeaders, requestFilter);
   chrome.webRequest.onCompleted.addListener(forgetHeaders, requestFilter);
   chrome.webRequest.onErrorOccurred.addListener(forgetHeaders, requestFilter);
@@ -105,7 +117,7 @@ chrome.runtime.onConnect.addListener(function onReceivePort(port) {
         urls: [data.requestUrl],
         types: ['xmlhttprequest'],
         tabId: tabId,
-      }, ['blocking', 'requestHeaders']);
+      }, ['blocking', ...extraInfoSpecWithHeaders]);
     }
     // Acknowledge the message, and include the latest referer for this frame.
     port.postMessage(referer);