Reduce the number of calls to Browser.GetSystemInfo.

While adding some debug logging, it was discovered that hundreds of
calls to this API were being made upon browser restart while building
the TestExpectations cache. Cache the result.

TBR=caseq@chromium.org

Bug: 797368
Cq-Include-Trybots: master.tryserver.chromium.android:android_optional_gpu_tests_rel;master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel
Change-Id: Ic3ae33928e90759ce933b93a74abb897e4a1fb51
Reviewed-on: https://chromium-review.googlesource.com/879752
Commit-Queue: Kenneth Russell <kbr@chromium.org>
Reviewed-by: Kenneth Russell <kbr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#531147}
1 file changed