Make stream captures work on canvases that are not in the DOM.

third_party/WebKit/Source/platform/graphics/ImageBuffer.cpp

Index: third_party/WebKit/Source/platform/graphics/ImageBuffer.cpp
diff --git a/third_party/WebKit/Source/platform/graphics/ImageBuffer.cpp b/third_party/WebKit/Source/platform/graphics/ImageBuffer.cpp
index 503ca1b68bf770bcf2bd21f84d035740686197fd..f4e3248d600dc046d18d62d078acb113b362f420 100644
--- a/third_party/WebKit/Source/platform/graphics/ImageBuffer.cpp
+++ b/third_party/WebKit/Source/platform/graphics/ImageBuffer.cpp
@@ -150,18 +150,12 @@ bool ImageBuffer::isSurfaceValid() const {
   return m_surface->isValid();
 }
 
-bool ImageBuffer::isDirty() {
-  return m_client ? m_client->isDirty() : false;
+void ImageBuffer::finalizeFrame() {
+  m_surface->finalizeFrame();
 }
 
-void ImageBuffer::didFinalizeFrame() {
-  if (m_client)
-    m_client->didFinalizeFrame();
-}
-
-void ImageBuffer::finalizeFrame(const FloatRect& dirtyRect) {
-  m_surface->finalizeFrame(dirtyRect);
-  didFinalizeFrame();

[xlai (Olivia), 2017/02/08 17:58:40]

Great works. The previous logic flow was a bit messy as HTMLCanvasElement calls
this function and this function routes back to
HTMLCanvasElement::didFinalizeFrame() via m_client.

[Justin Novosad, 2017/02/08 18:43:12]

Exactly. I got rid of the zig-zag flow we had before.

+void ImageBuffer::doPaintInvalidation(const FloatRect& dirtyRect) {
+  m_surface->doPaintInvalidation(dirtyRect);
 }
 
 bool ImageBuffer::restoreSurface() const {