Refactor the PlatformContext layer to have only one class.

Previously we had three classes of PlatformCanvas*, one for each platform. Then
we had a typedef of PlatformContext to PlatformCanvas[Mac|Win|Linux] for the
specific platform.

This means that it was almost impossible to forward-declare PlatformCanvas and
there were a bunch of unnecessary includes of platform_canvas.h in header
files.

This change makes there be only one platform_canvas.h header with ifdefs, which
removes a decent amount of duplicated code. There is a platform-independent
file, and one platform-dependent file of platform_canvas for each platform.

I also renamed PlatformDevice[Mac|Win|Linux] to PlatformDevice, althouth in
this case I kept the separate headers since there was much less overlap.

I also broke out CanvasPaint into separate headers so this template doesn't
need to be included all over the project (only a couple of files actually need
it).

Review URL: http://codereview.chromium.org/125109

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@18363 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 26 insertions, 0 deletions

diff --git a/skia/ext/platform_canvas.cc b/skia/ext/platform_canvas.cc
new file mode 100644
index 0000000..9121a0d
--- /dev/null
+++ b/skia/ext/platform_canvas.cc
@@ -0,0 +1,26 @@
+// Copyright (c) 2006-2008 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 "skia/ext/platform_canvas.h"
+#include "third_party/skia/include/core/SkTypes.h"
+
+namespace skia {
+
+SkDevice* PlatformCanvas::setBitmapDevice(const SkBitmap&) {
+  SkASSERT(false);  // Should not be called.
+  return NULL;
+}
+
+PlatformDevice& PlatformCanvas::getTopPlatformDevice() const {
+  // All of our devices should be our special PlatformDevice.
+  SkCanvas::LayerIter iter(const_cast<PlatformCanvas*>(this), false);
+  return *static_cast<PlatformDevice*>(iter.device());
+}
+
+// static
+size_t PlatformCanvas::StrideForWidth(unsigned width) {
+  return 4 * width;
+}
+
+}  // namespace skia