Add the ability for the GPU process to be used to paint the backing store of a

tab. This is the first pass and is currently a bit buggy and incomplete.

This patch refactors the backing store to make it a virtual interface which is
then implemented by the platform-specific backing stores. This cleans up the
multi-platform aspects of the old code, and also makes it possible to create
different backing stores (such as ones in another process).

This renames the BackingStore::PaintRect function to PaintToBackingStore which
clears up what it does. I would often get confused and think that it paints
the backing store to the screen.

This makes a common way to capture backing store information and adds it to the
backing store API. This removed a bunch of ugly ifdefs.

This adds the ability for a backing store to specify that the TransportDIB
should not be freed by RenderWidgetHost when painting is complete. This is
necessary since the out-of-process version needs to use it after the
RenderWidget paint function has returned.

This pushes up the vector of copy_rect from RenderWidgetHost to the actual
BackingStores. This prevents us from sending duplicate data over IPC. It also
makes the common non-IPC case more efficient, since we end up setting up various
surfaces only once when there are multiple update rects.

BUG=none
TEST=none
Review URL: http://codereview.chromium.org/523028

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@36075 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 64 insertions, 2 deletions

diff --git a/chrome/browser/renderer_host/test/test_backing_store.cc b/chrome/browser/renderer_host/test/test_backing_store.cc
new file mode 100644
index 0000000..d90c7fd
--- /dev/null
+++ b/chrome/browser/renderer_host/test/test_backing_store.cc
@@ -0,0 +1,31 @@
+// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/renderer_host/test/test_backing_store.h"
+
+TestBackingStore::TestBackingStore(RenderWidgetHost* widget,
+                                   const gfx::Size& size)
+    : BackingStore(widget, size) {
+}
+
+TestBackingStore::~TestBackingStore() {
+}
+
+void TestBackingStore::PaintToBackingStore(
+    RenderProcessHost* process,
+    TransportDIB::Id bitmap,
+    const gfx::Rect& bitmap_rect,
+    const std::vector<gfx::Rect>& copy_rects,
+    bool* painted_synchronously) {
+}
+
+bool TestBackingStore::CopyFromBackingStore(const gfx::Rect& rect,
+                                            skia::PlatformCanvas* output) {
+  return false;
+}
+
+void TestBackingStore::ScrollBackingStore(int dx, int dy,
+                                          const gfx::Rect& clip_rect,
+                                          const gfx::Size& view_size) {
+}
diff --git a/chrome/browser/renderer_host/test/test_backing_store.h b/chrome/browser/renderer_host/test/test_backing_store.h
new file mode 100644
index 0000000..41deb4c
--- /dev/null
+++ b/chrome/browser/renderer_host/test/test_backing_store.h
@@ -0,0 +1,31 @@
+// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_BROWSER_RENDERER_HOST_TEST_TEST_BACKING_STORE_H_
+#define CHROME_BROWSER_RENDERER_HOST_TEST_TEST_BACKING_STORE_H_
+
+#include "base/basictypes.h"
+#include "chrome/browser/renderer_host/backing_store.h"
+
+class TestBackingStore : public BackingStore {
+ public:
+  TestBackingStore(RenderWidgetHost* widget, const gfx::Size& size);
+  virtual ~TestBackingStore();
+
+  // BackingStore implementation.
+  virtual void PaintToBackingStore(RenderProcessHost* process,
+                                   TransportDIB::Id bitmap,
+                                   const gfx::Rect& bitmap_rect,
+                                   const std::vector<gfx::Rect>& copy_rects,
+                                   bool* painted_synchronously);
+  virtual bool CopyFromBackingStore(const gfx::Rect& rect,
+                                    skia::PlatformCanvas* output);
+  virtual void ScrollBackingStore(int dx, int dy,
+                                  const gfx::Rect& clip_rect,
+                                  const gfx::Size& view_size);
+ private:
+  DISALLOW_COPY_AND_ASSIGN(TestBackingStore);
+};
+
+#endif  // CHROME_BROWSER_RENDERER_HOST_TEST_TEST_BACKING_STORE_H_
diff --git a/chrome/browser/renderer_host/test/test_render_view_host.cc b/chrome/browser/renderer_host/test/test_render_view_host.cc
index 720f51e..095c2e1 100644
--- a/chrome/browser/renderer_host/test/test_render_view_host.cc
+++ b/chrome/browser/renderer_host/test/test_render_view_host.cc
@@ -5,7 +5,7 @@
 #include "chrome/browser/renderer_host/test/test_render_view_host.h"
 
 #include "base/gfx/rect.h"
-#include "chrome/browser/renderer_host/backing_store.h"
+#include "chrome/browser/renderer_host/test/test_backing_store.h"
 #include "chrome/browser/tab_contents/test_tab_contents.h"
 #include "chrome/common/render_messages.h"
 
@@ -74,7 +74,7 @@ TestRenderWidgetHostView::TestRenderWidgetHostView(RenderWidgetHost* rwh)
 
 BackingStore* TestRenderWidgetHostView::AllocBackingStore(
     const gfx::Size& size) {
-  return new BackingStore(rwh_, size);
+  return new TestBackingStore(rwh_, size);
 }
 
 #if defined(OS_MACOSX)