Move uncoupled code out of skia/ext/platform_device.h

skia/ext/platform_canvas.cc

Index: skia/ext/platform_canvas.cc
diff --git a/skia/ext/platform_canvas.cc b/skia/ext/platform_canvas.cc
index cf362b3ce3a3f95fad61c51db39d9b355db93514..0df64962bbcc7938e6bf04e67b0b6982418479f9 100644
--- a/skia/ext/platform_canvas.cc
+++ b/skia/ext/platform_canvas.cc
@@ -4,9 +4,33 @@
 
 #include "skia/ext/platform_canvas.h"
 
+#include "base/logging.h"
 #include "skia/ext/bitmap_platform_device.h"
+#include "skia/ext/platform_device.h"
+#include "third_party/skia/include/core/SkMetaData.h"
 #include "third_party/skia/include/core/SkTypes.h"
 
+namespace {
+
+#if defined(OS_MACOSX)
+const char kIsPreviewMetafileKey[] = "CrIsPreviewMetafile";
+#endif
+
+void SetBoolMetaData(const SkCanvas& canvas, const char* key,  bool value) {
+  SkMetaData& meta = skia::GetMetaData(canvas);
+  meta.setBool(key, value);
+}
+
+bool GetBoolMetaData(const SkCanvas& canvas, const char* key) {
+  bool value;
+  SkMetaData& meta = skia::GetMetaData(canvas);
+  if (!meta.findBool(key, &value))
+    value = false;
+  return value;
+}
+
+}  // namespace
+
 namespace skia {
 
 SkBaseDevice* GetTopDevice(const SkCanvas& canvas) {
@@ -77,9 +101,34 @@ SkCanvas* CreateCanvas(const skia::RefPtr<SkBaseDevice>& device, OnFailureType f
   if (!device) {
     if (CRASH_ON_FAILURE == failureType)
       SK_CRASH();
-    return NULL;
+    return nullptr;
   }
   return new SkCanvas(device.get());
 }
 
+SkMetaData& GetMetaData(const SkCanvas& canvas) {
+  SkBaseDevice* device = canvas.getDevice();
+  DCHECK(device != nullptr);
+  return device->getMetaData();
+}
+
+#if defined(OS_MACOSX)
+void SetIsPreviewMetafile(const SkCanvas& canvas, bool is_preview) {
+  SetBoolMetaData(canvas, kIsPreviewMetafileKey, is_preview);
+}
+
+bool IsPreviewMetafile(const SkCanvas& canvas) {
+  return GetBoolMetaData(canvas, kIsPreviewMetafileKey);
+}
+
+CGContextRef GetBitmapContext(const SkCanvas& canvas) {
+  SkBaseDevice* device = GetTopDevice(canvas);
+  PlatformDevice* platform_device = GetPlatformDevice(device);
+  return platform_device ?  platform_device->GetBitmapContext() :
+      nullptr;
+}
+
+#endif
+
+
 }  // namespace skia