Move clip off of draw target

src/gpu/GrClip.cpp

Index: src/gpu/GrClip.cpp
diff --git a/src/gpu/GrClip.cpp b/src/gpu/GrClip.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..761c065460af4c9b0adecaf7a54cf26801000148
--- /dev/null
+++ b/src/gpu/GrClip.cpp
@@ -0,0 +1,50 @@
+/*
+ * Copyright 2010 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "GrClip.h"
+
+#include "GrSurface.h"
+#include "SkRect.h"
+
+///////////////////////////////////////////////////////////////////////////////
+
+/**
+ * getConservativeBounds returns the conservative bounding box of the clip
+ * in device (as opposed to canvas) coordinates. If the bounding box is
+ * the result of purely intersections of rects (with an initial replace)
+ * isIntersectionOfRects will be set to true.
+ */
+void GrClip::getConservativeBounds(int width, int height, SkIRect* devResult,
+                                   bool* isIntersectionOfRects) const {
+    switch (fClipType) {
+        default:
+            SkFAIL("incomplete switch\n");
+        case kWideOpen_ClipType: {
+            devResult->setLTRB(0, 0, SkIntToScalar(width), SkIntToScalar(height));
+            if (isIntersectionOfRects) {
+                *isIntersectionOfRects = false;

[bsalomon, 2015/02/23 19:31:29]

I think we should say true here... it is effectively just an intersect with
SkRect::MakeWH(width, height);

+            }
+        } break;
+        case kIRect_ClipType: {
+            *devResult = this->irect();
+            if (isIntersectionOfRects) {
+                *isIntersectionOfRects = false;

[bsalomon, 2015/02/23 19:31:29]

true

+            }
+        } break;
+        case kClipStack_ClipType: {
+            SkRect devBounds;
+            this->clipStack()->getConservativeBounds(-this->origin().fX,
+                                                     -this->origin().fY,
+                                                     width,
+                                                     height,
+                                                     &devBounds,
+                                                     isIntersectionOfRects);
+            devBounds.roundOut(devResult);
+        } break;
+
+    }
+}