Reland of placing allocate bitmap IPC messages with a new Mojo interface.

content/child/child_shared_bitmap_manager.h

Index: content/child/child_shared_bitmap_manager.h
diff --git a/content/child/child_shared_bitmap_manager.h b/content/child/child_shared_bitmap_manager.h
index feb065bb92a433fb64f549e3c5fd10d27e3ba37e..b63d3e50a11493b73aaa3455a5a1afefbb224aaa 100644
--- a/content/child/child_shared_bitmap_manager.h
+++ b/content/child/child_shared_bitmap_manager.h
@@ -13,7 +13,8 @@
 #include "base/memory/ref_counted.h"
 #include "base/memory/shared_memory.h"
 #include "cc/resources/shared_bitmap_manager.h"
-#include "content/child/thread_safe_sender.h"
+#include "content/common/render_message_filter.mojom.h"
+#include "mojo/public/cpp/bindings/thread_safe_interface_ptr.h"
 
 namespace content {
 
@@ -31,7 +32,9 @@
 
 class ChildSharedBitmapManager : public cc::SharedBitmapManager {
  public:
-  ChildSharedBitmapManager(scoped_refptr<ThreadSafeSender> sender);
+  explicit ChildSharedBitmapManager(
+      const scoped_refptr<mojom::ThreadSafeRenderMessageFilterAssociatedPtr>&
+          render_message_filter_ptr);
   ~ChildSharedBitmapManager() override;
 
   // cc::SharedBitmapManager implementation.
@@ -43,11 +46,13 @@
 
   std::unique_ptr<cc::SharedBitmap> GetBitmapForSharedMemory(
       base::SharedMemory* mem);
-  std::unique_ptr<SharedMemoryBitmap> AllocateSharedMemoryBitmap(
-      const gfx::Size& size);
 
  private:
-  scoped_refptr<ThreadSafeSender> sender_;
+  void NotifyAllocatedSharedBitmap(base::SharedMemory* memory,
+                                   const cc::SharedBitmapId& id);
+
+  scoped_refptr<mojom::ThreadSafeRenderMessageFilterAssociatedPtr>
+      render_message_filter_ptr_;
 
   DISALLOW_COPY_AND_ASSIGN(ChildSharedBitmapManager);
 };