Refactoring of GPU NormalMap handling out into its own class

src/core/SkBitmapProcShader.cpp

Index: src/core/SkBitmapProcShader.cpp
diff --git a/src/core/SkBitmapProcShader.cpp b/src/core/SkBitmapProcShader.cpp
index c86dfdd98970a02d616874ba0aa0f0ec276c2b40..b2dee0b9d27fc13ed471fec619e3963ef9c36006 100644
--- a/src/core/SkBitmapProcShader.cpp
+++ b/src/core/SkBitmapProcShader.cpp
@@ -305,6 +305,12 @@ bool SkBitmapProcShader::isOpaque() const {
     return fRawBitmap.isOpaque();
 }
 
+bool SkBitmapProcShader::BitmapIsTooBig(const SkBitmap& bm) {
+    static const int kMaxSize = 65535;
+
+    return bm.width() > kMaxSize || bm.height() > kMaxSize;
+}
+
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 
 #include "SkUnPreMultiply.h"