NoSaveLayerCanvas now its own file

src/utils/SkNoSaveLayerCanvas.h

+/*
+ * Copyright 2014 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkNoSaveLayerCanvas_DEFINED
+#define SkNoSaveLayerCanvas_DEFINED
+
+#include "SkCanvas.h"
+#include "SkRRect.h"
+
+// The NoSaveLayerCanvas is used to play back SkPictures when the saveLayer
+// functionality isn't required (e.g., during analysis of the draw calls).
+// It also simplifies the clipping calls to only use rectangles.
+class SkNoSaveLayerCanvas : public SkCanvas {
+public:
+    SkNoSaveLayerCanvas(SkBaseDevice* device) : INHERITED(device) {}
+
+    // turn saveLayer() into save() for speed, should not affect correctness.
+    virtual int saveLayer(const SkRect* bounds, 
+                          const SkPaint* paint,
+                          SaveFlags flags) SK_OVERRIDE {
+
+        // Like SkPictureRecord, we don't want to create layers, but we do need
+        // to respect the save and (possibly) its rect-clip.
+        int count = this->INHERITED::save(flags);
+        if (NULL != bounds) {
+            this->INHERITED::clipRectBounds(bounds, flags, NULL);
+        }
+        return count;
+    }
+
+    // disable aa for speed
+    virtual bool clipRect(const SkRect& rect, 
+                          SkRegion::Op op,
+                          bool doAA) SK_OVERRIDE {
+        return this->INHERITED::clipRect(rect, op, false);
+    }
+
+    // for speed, just respect the bounds, and disable AA. May give us a few
+    // false positives and negatives.
+    virtual bool clipPath(const SkPath& path, 
+                          SkRegion::Op op,
+                          bool doAA) SK_OVERRIDE {
+        return this->updateClipConservativelyUsingBounds(path.getBounds(), op, 
+                                                         path.isInverseFillType());
+    }
+    virtual bool clipRRect(const SkRRect& rrect, 
+                           SkRegion::Op op,
+                           bool doAA) SK_OVERRIDE {
+        return this->updateClipConservativelyUsingBounds(rrect.getBounds(), op, false);
+    }
+
+private:
+    typedef SkCanvas INHERITED;
+};
+
+#endif // SkNoSaveLayerCanvas_DEFINED