Update use of SkCanvas and SkDevice to match change in Skia

skia/ext/bitmap_platform_device_mac.cc

Index: skia/ext/bitmap_platform_device_mac.cc
diff --git a/skia/ext/bitmap_platform_device_mac.cc b/skia/ext/bitmap_platform_device_mac.cc
index 841c75a84d52d413a9e631ed9066f835230db851..a48228324d987b5a50f2add07d31927ad64dc52d 100644
--- a/skia/ext/bitmap_platform_device_mac.cc
+++ b/skia/ext/bitmap_platform_device_mac.cc
@@ -49,6 +49,14 @@ static CGContextRef CGContextForData(void* data, int width, int height) {
 
 }  // namespace
 
+SkDevice* SkBitmapPlatformDeviceFactory::newDevice(SkBitmap::Config config,
+                                                   int width, int height,
+                                                   bool isOpaque,
+                                                   bool isForLayer) {
+  SkASSERT(config == SkBitmap::kARGB_8888_Config);
+  return BitmapPlatformDevice::Create(NULL, width, height, isOpaque);
+}
+
 BitmapPlatformDevice::BitmapPlatformDeviceData::BitmapPlatformDeviceData(
     CGContextRef bitmap)
     : bitmap_context_(bitmap),