Merge tomhudson and mtklein SkPaint shrinking approaches.

include/core/SkPaint.h

Index: include/core/SkPaint.h
diff --git a/include/core/SkPaint.h b/include/core/SkPaint.h
index abb859950c5bb6a66aecccded690ca8cd6ae02a2..bf0f91ceb25e896493afbb3c2e98f8291be56e13 100644
--- a/include/core/SkPaint.h
+++ b/include/core/SkPaint.h
@@ -980,6 +980,11 @@ public:
 
     SkDEVCODE(void toString(SkString*) const;)
 
+    struct FlatteningTraits {
+        static void Flatten(SkWriteBuffer& buffer, const SkPaint& paint);
+        static void Unflatten(SkReadBuffer& buffer, SkPaint* paint);
+    };
+
 private:
     SkTypeface*     fTypeface;
     SkScalar        fTextSize;
@@ -999,15 +1004,25 @@ private:
     SkColor         fColor;
     SkScalar        fWidth;
     SkScalar        fMiterLimit;
-    // all of these bitfields should add up to 32
-    unsigned        fFlags : 16;
-    unsigned        fTextAlign : 2;
-    unsigned        fCapType : 2;
-    unsigned        fJoinType : 2;
-    unsigned        fStyle : 2;
-    unsigned        fTextEncoding : 2;  // 3 values
-    unsigned        fHinting : 2;
-    //unsigned      fFreeBits : 4;
+
+    union {
+        struct {
+            // all of these bitfields should add up to 32
+            unsigned        fFlags : 16;
+            unsigned        fTextAlign : 2;
+            unsigned        fCapType : 2;
+            unsigned        fJoinType : 2;
+            unsigned        fStyle : 2;
+            unsigned        fTextEncoding : 2;  // 3 values
+            unsigned        fHinting : 2;
+            //unsigned      fFreeBits : 4;
+        };
+        uint32_t fBitfields;
+    };
+    uint32_t getBitfields() const { return fBitfields; }
+    void setBitfields(uint32_t bitfields);
+
+    uint32_t fDirtyBits;
 
 
     SkDrawCacheProc    getDrawCacheProc() const;