Replace WGC3D visibility extension with resource_usage extension. [Part 2 of 3]

content/common/gpu/image_transport_surface_win.cc

Index: content/common/gpu/image_transport_surface_win.cc
diff --git a/content/common/gpu/image_transport_surface_win.cc b/content/common/gpu/image_transport_surface_win.cc
index 9a8e549a72ff014d93a3ee4d655457ce70e712f1..b6fe4def84f26e99f05652715926cdeb34c86709 100644
--- a/content/common/gpu/image_transport_surface_win.cc
+++ b/content/common/gpu/image_transport_surface_win.cc
@@ -40,7 +40,7 @@ class PbufferImageTransportSurface
   virtual bool SwapBuffers() OVERRIDE;
   virtual bool PostSubBuffer(int x, int y, int width, int height) OVERRIDE;
   virtual std::string GetExtensions() OVERRIDE;
-  virtual void SetVisible(bool visible) OVERRIDE;
+  virtual void SetResourceUsage(ResourceUsage resourceUsage) OVERRIDE;
 
  protected:
   // ImageTransportSurface implementation
@@ -121,16 +121,21 @@ bool PbufferImageTransportSurface::PostSubBuffer(
   return false;
 }
 
-void PbufferImageTransportSurface::SetVisible(bool visible) {
-  if (visible == is_visible_)
-    return;
-
-  is_visible_ = visible;
-
-  if (visible)
-    Resize(visible_size_);
-  else
-    Resize(gfx::Size(1, 1));
+void PbufferImageTransportSurface::SetResourceUsage(
+    ResourceUsage resourceUsage) {
+  switch (resourceUsage) {
+    case RESOURCE_USAGE_FULL:
+      Resize(visible_size_);
+      is_visible_ = true;
+      break;
+    case RESOURCE_USAGE_LESS:
+      Resize(gfx::Size(1, 1));
+      is_visible_ = false;
+      break;
+    case RESOURCE_USAGE_NONE:
+      // TODO(mmocny): drop all the buffers
+      break;
+  }
 }
 
 std::string PbufferImageTransportSurface::GetExtensions() {