Removal of dependencies on PlatformDevice classes.

content/renderer/webplugin_delegate_proxy.cc

Index: content/renderer/webplugin_delegate_proxy.cc
===================================================================
--- content/renderer/webplugin_delegate_proxy.cc	(revision 85945)
+++ content/renderer/webplugin_delegate_proxy.cc	(working copy)
@@ -850,8 +850,9 @@
   int page_start_x = content_rect.x() - context_offset_x;
   int page_start_y = content_rect.y() - context_offset_y;
 
-  CGContextRef bg_context =
-      background_store_canvas_->getTopPlatformDevice().GetBitmapContext();
+  CGContextRef bg_context = skia::BeginPlatformPaint(
+      background_store_canvas_.get());
+
   DCHECK_EQ(CGBitmapContextGetBitsPerPixel(context),
             CGBitmapContextGetBitsPerPixel(bg_context));
   const unsigned char* bg_bytes = static_cast<const unsigned char*>(
@@ -869,9 +870,8 @@
   int page_start_x = static_cast<int>(page_x_double);
   int page_start_y = static_cast<int>(page_y_double);
 
-  skia::PlatformDevice& device =
-      background_store_canvas_->getTopPlatformDevice();
-  cairo_surface_t* bg_surface = cairo_get_target(device.BeginPlatformPaint());
+  cairo_surface_t* bg_surface =cairo_get_target(skia::BeginPlatformPaint(
+      background_store_canvas_.get()));
   DCHECK_EQ(cairo_surface_get_type(bg_surface), CAIRO_SURFACE_TYPE_IMAGE);
   DCHECK_EQ(cairo_image_surface_get_format(bg_surface), CAIRO_FORMAT_ARGB32);
   cairo_surface_flush(bg_surface);
@@ -905,9 +905,12 @@
     int bg_offset = bg_stride * bg_y + bg_x_byte_offset;
     if (memcmp(page_bytes + page_offset,
                bg_bytes + bg_offset,
-               damage_width * bytes_per_pixel) != 0)
+               damage_width * bytes_per_pixel) != 0) {
+      skia::EndPlatformPaint(background_store_canvas_.get());

[jamesr, 2011/05/19 22:20:52]

it seems that here and in other spots that it'd be really handy to have a
stack-allocated helper class to pair up the
skia::BeginPlatformPaint/skia::EndPlatformPaint() calls so you don't have to
worry about matching them by hand.

[Jeff Timanus, 2011/05/24 16:50:28]

I added ScopedPlatformPaint to skia\ext\platform_canvas.h to do exactly that. 
Also went through the code and changed paired calls to begin/end to make use of
the class.

       return true;
+    }
   }
+  skia::EndPlatformPaint(background_store_canvas_.get());
 #endif
 
   return false;