Pack and align SkStrokeRec to 4-byte boundary.

include/core/SkStrokeRec.h

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkStrokeRec_DEFINED
 #define SkStrokeRec_DEFINED
 
@@ skipping 17 matching lines @@
         kStroke_Style,
         kStrokeAndFill_Style
     };
     enum {
         kStyleCount = kStrokeAndFill_Style + 1
     };
 
     Style getStyle() const;
     SkScalar getWidth() const { return fWidth; }
     SkScalar getMiter() const { return fMiterLimit; }
-    SkPaint::Cap getCap() const { return fCap; }
-    SkPaint::Join getJoin() const { return fJoin; }
+    SkPaint::Cap getCap() const { return (SkPaint::Cap)fCap; }
+    SkPaint::Join getJoin() const { return (SkPaint::Join)fJoin; }
 
     bool isHairlineStyle() const {
         return kHairline_Style == this->getStyle();
     }
 
     bool isFillStyle() const {
         return kFill_Style == this->getStyle();
     }
 
     void setFillStyle();
@@ skipping 58 matching lines @@
                fJoin == other.fJoin &&
                fStrokeAndFill == other.fStrokeAndFill;
     }
 
 private:
     void init(const SkPaint&, SkPaint::Style, SkScalar resScale);
 
     SkScalar        fResScale;
     SkScalar        fWidth;
     SkScalar        fMiterLimit;
-    SkPaint::Cap    fCap;
-    SkPaint::Join   fJoin;
-    bool            fStrokeAndFill;
+    // The following three members are packed together into a single u32.
+    // This is to avoid unnecessary padding and ensure binary equality for
+    // hashing (because the padded areas might contain garbage values).
+    // 
+    // fCap and fJoin are larger than needed to avoid having to initialize
+    // any pad values
+    uint32_t        fCap : 16;             // SkPaint::Cap
+    uint32_t        fJoin : 15;            // SkPaint::Join
+    uint32_t        fStrokeAndFill : 1;    // bool
 };
 
 #endif