Free the dibsection (HBITMAP) in PlatformBitmap's destructor, so we don't leak!

This adds an extra slot to PlatformBitmap, which is implemented for all platforms. To
do this simply, an intptr_t field is added (platform_extra_) which is initialized to 0.
At the moment, only the windows port uses this, but there is no cost to the other ports.

BUG=158931
Review URL: https://codereview.chromium.org/11293036

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@165424 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 9 insertions, 2 deletions

diff --git a/skia/ext/bitmap_platform_device_win.cc b/skia/ext/bitmap_platform_device_win.cc
index 12b9266..dc21673 100644
--- a/skia/ext/bitmap_platform_device_win.cc
+++ b/skia/ext/bitmap_platform_device_win.cc
@@ -273,6 +273,10 @@ SkDevice* BitmapPlatformDevice::onCreateCompatibleDevice(
 PlatformBitmap::~PlatformBitmap() {
   if (surface_)
     DeleteDC(surface_);
+
+  HBITMAP hbitmap = (HBITMAP)platform_extra_;
+  if (hbitmap)
+    DeleteObject(hbitmap);
 }
 
 bool PlatformBitmap::Allocate(int width, int height, bool is_opaque) {
@@ -287,6 +291,8 @@ bool PlatformBitmap::Allocate(int width, int height, bool is_opaque) {
   // monochrome pixel wide and one monochrome pixel high. Since we select our
   // own bitmap, we must delete the previous one.
   DeleteObject(old_bitmap);
+  // remember the hbitmap, so we can free it in our destructor
+  platform_extra_ = (intptr_t)hbitmap;
   return true;
 }
 
diff --git a/skia/ext/platform_canvas.cc b/skia/ext/platform_canvas.cc
index 7e70165..11b1f5e 100644
--- a/skia/ext/platform_canvas.cc
+++ b/skia/ext/platform_canvas.cc
@@ -87,6 +87,6 @@ void MakeOpaque(SkCanvas* canvas, int x, int y, int width, int height) {
   canvas->drawRect(rect, paint);
 }
 
-PlatformBitmap::PlatformBitmap() : surface_(0) {}
+PlatformBitmap::PlatformBitmap() : surface_(0), platform_extra_(0) {}
 
 }  // namespace skia
diff --git a/skia/ext/platform_canvas.h b/skia/ext/platform_canvas.h
index 4d2b0c0..f20d62e 100644
--- a/skia/ext/platform_canvas.h
+++ b/skia/ext/platform_canvas.h
@@ -169,7 +169,8 @@ class SK_API PlatformBitmap {
 
  private:
   SkBitmap bitmap_;
-  PlatformSurface surface_;
+  PlatformSurface surface_; // initialized to 0
+  intptr_t platform_extra_; // initialized to 0, specific to each platform
 
   DISALLOW_COPY_AND_ASSIGN(PlatformBitmap);
 };