Fixed a few styles issues in skia::PlatformDevice. Made function names consistent. Added Begin/En...

skia/ext/platform_device_mac.cc

Index: skia/ext/platform_device_mac.cc
===================================================================
--- skia/ext/platform_device_mac.cc	(revision 80484)
+++ skia/ext/platform_device_mac.cc	(working copy)
@@ -40,6 +40,14 @@
     return true;
 }
 
+CGContextRef PlatformDevice::BeginPlatformPaint() {
+  return GetBitmapContext();
+}
+
+void PlatformDevice::EndPlatformPaint() {
+  // Flushing will be done in onAccessBitmap.
+}
+
 // Set up the CGContextRef for peaceful coexistence with Skia
 void PlatformDevice::InitializeCGContext(CGContextRef context) {
   // CG defaults to the same settings as Skia