Remove getter of writable GrEffectStage from GrDrawState.

Upcoming changes will require GrDrawState to know things about the set of installed effects. Thus all setting of effects must go through a GrDrawState function (setEffect()). This change accomplishes that.
Review URL: https://codereview.appspot.com/7214045

git-svn-id: http://skia.googlecode.com/svn/trunk@7411 2bbb7eff-a529-9590-31e7-b0007b416f81

1 files changed, 11 insertions, 8 deletions

diff --git a/include/gpu/GrContext.h b/include/gpu/GrContext.h
index 556893895a..98683a475c 100644
--- a/include/gpu/GrContext.h
+++ b/include/gpu/GrContext.h
@@ -910,14 +910,17 @@ private:
     // for use with textures released from an GrAutoScratchTexture.
     void addExistingTextureToCache(GrTexture* texture);
 
-    bool installPMToUPMEffect(GrTexture* texture,
-                              bool swapRAndB,
-                              const SkMatrix& matrix,
-                              GrEffectStage* stage);
-    bool installUPMToPMEffect(GrTexture* texture,
-                              bool swapRAndB,
-                              const SkMatrix& matrix,
-                              GrEffectStage* stage);
+    /** 
+     * These functions create premul <-> unpremul effects if it is possible to generate a pair
+     * of effects that make a readToUPM->writeToPM->readToUPM cycle invariant. Otherwise, they
+     * return NULL.
+     */
+    const GrEffectRef* createPMToUPMEffect(GrTexture* texture,
+                                           bool swapRAndB,
+                                           const SkMatrix& matrix);
+    const GrEffectRef* createUPMToPMEffect(GrTexture* texture,
+                                           bool swapRAndB,
+                                           const SkMatrix& matrix);
 
     typedef GrRefCnt INHERITED;
 };