Flag --incompatible_no_implicit_file_export will break projects in Bazel 1.2.1

[junyer]

50+ issues have just been filed across the projects using Bazel CI, but I don't believe that the errors are the fault of the projects themselves. For example, looking at the errors for RE2:

(03:11:36) ERROR: /var/lib/buildkite-agent/.cache/bazel/_bazel_buildkite-agent/eb235e6eaff3efa5936294d9cccba44f/external/bazel_tools/tools/test/CoverageOutputGenerator/java/com/google/devtools/coverageoutputgenerator/BUILD:4:1: in java_import rule @bazel_tools//tools/test/CoverageOutputGenerator/java/com/google/devtools/coverageoutputgenerator:all_lcov_merger_lib: target '@remote_coverage_tools//:all_lcov_merger_tools_deploy.jar' is not visible from target '@bazel_tools//tools/test/CoverageOutputGenerator/java/com/google/devtools/coverageoutputgenerator:all_lcov_merger_lib'. Check the visibility declaration of the former target if you think the dependency is legitimate
(03:11:36) ERROR: /var/lib/buildkite-agent/.cache/bazel/_bazel_buildkite-agent/eb235e6eaff3efa5936294d9cccba44f/external/bazel_tools/tools/jdk/BUILD:225:1: in java_import rule @bazel_tools//tools/jdk:JacocoCoverageRunner: target '@remote_java_tools_linux//:java_tools/JacocoCoverage_jarjar_deploy.jar' is not visible from target '@bazel_tools//tools/jdk:JacocoCoverageRunner'. Check the visibility declaration of the former target if you think the dependency is legitimate

[fweikert]

Not sure who's going to work on the underlying error, but there's a FR to make the notification script smarter wrt dependencies: #891