Allow one GPU crash per 5 minutes.

Currently we only allow one GPU process crash per hour. This leads
to some users losing GPU acceleration unnecessarily.

This CL makes us more forgiving.

BUG=1138597
TEST=bots
R=kbr@chromium.org

Change-Id: I26b0bbc33b69cc81a62d5ce5f31e5c5aa5ce29bd
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2472905Reviewed-by: Kenneth Russell <kbr@chromium.org>
Commit-Queue: Kenneth Russell <kbr@chromium.org>
Commit-Queue: Zhenyao Mo <zmo@chromium.org>
Auto-Submit: Zhenyao Mo <zmo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#817238}

content/browser/gpu/gpu_process_host.cc

@@ -152,7 +152,9 @@ const char* GetProcessLifetimeUmaName(gpu::GpuMode gpu_mode) {
 }
 
 // Forgive one GPU process crash after this many minutes.
-constexpr int kForgiveGpuCrashMinutes = 60;
+// This value should not be too small because then Chrome could end up in an
+// endless loop where it hangs and gets killed by GPU watchdog and hangs again.
+constexpr int kForgiveGpuCrashMinutes = 5;
 
 // Forgive one GPU process crash, when the GPU process is launched to run only
 // the display compositor, after this many minutes.