Allow RecordingImageBufferSurface to prevent fallback.

third_party/WebKit/Source/core/html/HTMLCanvasElement.cpp

Index: third_party/WebKit/Source/core/html/HTMLCanvasElement.cpp
diff --git a/third_party/WebKit/Source/core/html/HTMLCanvasElement.cpp b/third_party/WebKit/Source/core/html/HTMLCanvasElement.cpp
index 03686dab01763ef6d5253560ef7a9aedfad54bcb..686f2ada187a97216ac8c8b2d231486b72b5a9d9 100644
--- a/third_party/WebKit/Source/core/html/HTMLCanvasElement.cpp
+++ b/third_party/WebKit/Source/core/html/HTMLCanvasElement.cpp
@@ -953,7 +953,8 @@ HTMLCanvasElement::CreateUnacceleratedImageBufferSurface(
     OpacityMode opacity_mode) {
   if (ShouldUseDisplayList()) {
     auto surface = WTF::MakeUnique<RecordingImageBufferSurface>(
-        Size(), opacity_mode, context_->color_params());
+        Size(), RecordingImageBufferSurface::kAllowFallback, opacity_mode,

[pdr., 2017/04/25 23:00:27]

Should UnacceleratedImageBufferSurface also take an allow fallback parameter? Do
we need to allow fallback for the UnacceleratedImageBufferSurface surface
created a few lines below?

[Justin Novosad, 2017/04/26 14:25:25]

No, there is no fallback functionality in UnacceleratedImageBufferSurface

+        context_->color_params());
     if (surface->IsValid()) {
       CanvasMetrics::CountCanvasContextUsage(
           CanvasMetrics::kDisplayList2DCanvasImageBufferCreated);