Calculate rough approximations for nvpr path sizes

src/gpu/gl/GrGLPath.h

Index: src/gpu/gl/GrGLPath.h
diff --git a/src/gpu/gl/GrGLPath.h b/src/gpu/gl/GrGLPath.h
index 935a2e24ad090b641d54211f52b6b27cd644de25..7ce93c61e184cbc96247253003c1dfb2c0cb4c9f 100644
--- a/src/gpu/gl/GrGLPath.h
+++ b/src/gpu/gl/GrGLPath.h
@@ -22,17 +22,20 @@ class GrGpuGL;
 
 class GrGLPath : public GrPath {
 public:
-    static void InitPathObject(GrGpuGL*,
-                               GrGLuint pathID,
-                               const SkPath&,
-                               const SkStrokeRec&);
+    /**
+     * Initialize a GL path object with a given path and stroke.
+     *
+     * @return the approximate GPU memory size of the path object in bytes.
+     */
+    static size_t InitPathObject(GrGpuGL*,
+                                 GrGLuint pathID,
+                                 const SkPath&,
+                                 const SkStrokeRec&);
 
     GrGLPath(GrGpuGL* gpu, const SkPath& path, const SkStrokeRec& stroke);
     virtual ~GrGLPath();
     GrGLuint pathID() const { return fPathID; }
-    // TODO: Figure out how to get an approximate size of the path in Gpu
-    // memory.
-    virtual size_t gpuMemorySize() const SK_OVERRIDE { return 100; }
+    virtual size_t gpuMemorySize() const SK_OVERRIDE { return fGpuMemorySize; }
 
 protected:
     virtual void onRelease() SK_OVERRIDE;
@@ -40,6 +43,7 @@ protected:
 
 private:
     GrGLuint fPathID;
+    size_t fGpuMemorySize;
 
     typedef GrPath INHERITED;
 };