add new onClip* methods to SkCanvas

The goal of this CL is to add new onClip* methods that disassociate reporting on the state of the clip from the clip operations themselves. This is because, for some backends (e.g., the GPU), incrementally tracking the state of the clip creates some overhead. 

Once Chromium is moved over to the new API, the SkCanvas::clip* methods will be made non-virtual.

[reed1, 2014-02-27 18:43:50]

lgtm w/ question about virtualization

https://codereview.chromium.org/183453002/diff/30001/include/core/SkCanvas.h
File include/core/SkCanvas.h (right):

https://codereview.chromium.org/183453002/diff/30001/include/core/SkCanvas.h#...
include/core/SkCanvas.h:981: virtual bool isClipEmpty() const;
Why does this need to be virtual, but not (also) getClipType()?

[robertphillips, 2014-02-27 20:20:30]

https://codereview.chromium.org/183453002/diff/30001/include/core/SkCanvas.h
File include/core/SkCanvas.h (right):

https://codereview.chromium.org/183453002/diff/30001/include/core/SkCanvas.h#...
include/core/SkCanvas.h:981: virtual bool isClipEmpty() const;
I learned about a new canvas entry point today. Please see new patch.

[robertphillips, 2014-02-28 14:30:06]

The CQ bit was checked by robertphillips@google.com

[commit-bot: I haz the power, 2014-02-28 14:30:19]

CQ is trying da patch. Follow status at
https://skia-tree-status.appspot.com/cq/robertphillips@google.com/183453002/5...

[commit-bot: I haz the power, 2014-02-28 14:30:26]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-02-28 14:30:27]

Failed to apply patch for src/utils/debugger/SkDebugCanvas.h:
While running patch -p0 --forward --force --no-backup-if-mismatch;
  patching file src/utils/debugger/SkDebugCanvas.h
  Hunk #2 FAILED at 223.
  1 out of 2 hunks FAILED -- saving rejects to file
src/utils/debugger/SkDebugCanvas.h.rej

Patch:       src/utils/debugger/SkDebugCanvas.h
Index: src/utils/debugger/SkDebugCanvas.h
===================================================================
--- src/utils/debugger/SkDebugCanvas.h	(revision 13577)
+++ src/utils/debugger/SkDebugCanvas.h	(working copy)
@@ -143,16 +143,6 @@
 
     virtual void clear(SkColor) SK_OVERRIDE;
 
-    virtual bool clipPath(const SkPath&, SkRegion::Op, bool) SK_OVERRIDE;
-
-    virtual bool clipRect(const SkRect&, SkRegion::Op, bool) SK_OVERRIDE;
-
-    virtual bool clipRRect(const SkRRect& rrect,
-                           SkRegion::Op op = SkRegion::kIntersect_Op,
-                           bool doAntiAlias = false) SK_OVERRIDE;
-
-    virtual bool clipRegion(const SkRegion& region, SkRegion::Op op)
SK_OVERRIDE;
-
     virtual bool concat(const SkMatrix& matrix) SK_OVERRIDE;
 
     virtual void drawBitmap(const SkBitmap&, SkScalar left, SkScalar top,
@@ -233,9 +223,31 @@
     static const int kVizImageHeight = 256;
     static const int kVizImageWidth = 256;
 
+    virtual bool isClipEmpty() const SK_OVERRIDE { return false; }
+    virtual ClipType getClipType() const SK_OVERRIDE { return kRect_ClipType; }
+    virtual bool getClipBounds(SkRect* bounds) const SK_OVERRIDE {
+        if (NULL != bounds) {
+            bounds->setXYWH(0, 0, 
+                            SkIntToScalar(this->imageInfo().fWidth), 
+                            SkIntToScalar(this->imageInfo().fHeight));
+        }
+        return true;
+    }
+    virtual bool getClipDeviceBounds(SkIRect* bounds) const SK_OVERRIDE {
+        if (NULL != bounds) {
+            bounds->setLargest();
+        }
+        return true;
+    }
+
 protected:
     virtual void onDrawDRRect(const SkRRect&, const SkRRect&, const SkPaint&)
SK_OVERRIDE;
 
+    virtual void onClipRect(const SkRect&, SkRegion::Op, ClipEdgeStyle)
SK_OVERRIDE;
+    virtual void onClipRRect(const SkRRect&, SkRegion::Op, ClipEdgeStyle)
SK_OVERRIDE;
+    virtual void onClipPath(const SkPath&, SkRegion::Op, ClipEdgeStyle)
SK_OVERRIDE;
+    virtual void onClipRegion(const SkRegion& region, SkRegion::Op)
SK_OVERRIDE;
+
 private:
     SkTDArray<SkDrawCommand*> fCommandVector;
     int fWidth;

[robertphillips, 2014-02-28 14:36:04]

committed as r13620

[robertphillips, 2014-02-28 15:29:00]

This was reverted in r13622 due to broken Chrome Canary compilation and failing
tilegrid tests

[robertphillips, 2014-02-28 18:20:02]

Relanded (with fixes) as r13627