Cleanup namespace usage in platform/graphics/[G-S]*

Source/platform/graphics/LoggingCanvas.cpp

Index: Source/platform/graphics/LoggingCanvas.cpp
diff --git a/Source/platform/graphics/LoggingCanvas.cpp b/Source/platform/graphics/LoggingCanvas.cpp
index de545d2f565910e699002d316bc7ad47e793ee21..d217aaa23db7564b49b6b1713c8a5e9bada59188 100644
--- a/Source/platform/graphics/LoggingCanvas.cpp
+++ b/Source/platform/graphics/LoggingCanvas.cpp
@@ -624,7 +624,7 @@ PassRefPtr<JSONObject> LoggingCanvas::objectForBitmapData(const SkBitmap& bitmap
 {
     RefPtr<JSONObject> dataItem = JSONObject::create();
     Vector<unsigned char> output;
-    blink::PNGImageEncoder::encode(bitmap, &output);
+    PNGImageEncoder::encode(bitmap, &output);
     dataItem->setString("base64", WTF::base64Encode(reinterpret_cast<char*>(output.data()), output.size()));
     dataItem->setString("mimeType", "image/png");
     return dataItem.release();
@@ -872,4 +872,5 @@ String LoggingCanvas::stringForText(const void* text, size_t byteLength, const S
         return "?";
     }
 }
-}
+
+} // namespace blink