Enable accelerated video in webtests

Bug: 1045248
Change-Id: I3afe8fc7690a3c48fd3710e265a3e7814cab9da3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2296491Reviewed-by: Zhenyao Mo <zmo@chromium.org>
Commit-Queue: Eugene Zemtsov <eugene@chromium.org>
Cr-Commit-Position: refs/heads/master@{#788584}

gpu/config/gpu_util.cc

@@ -310,8 +310,11 @@ GpuFeatureStatus GetFlashStage3DBaselineFeatureStatus(
 GpuFeatureStatus GetAcceleratedVideoDecodeFeatureStatus(
     const std::set<int>& blocklisted_features,
     bool use_swift_shader) {
-  if (use_swift_shader)
-    return kGpuFeatureStatusDisabled;
+  if (use_swift_shader) {
+    // This is for testing only. Chrome should exercise the GPU accelerated
+    // path on top of SwiftShader driver.
+    return kGpuFeatureStatusEnabled;
+  }
   if (blocklisted_features.count(GPU_FEATURE_TYPE_ACCELERATED_VIDEO_DECODE))
     return kGpuFeatureStatusBlocklisted;
   return kGpuFeatureStatusEnabled;