Plumb in flag for reusing scratch textures

include/gpu/GrContext.h

Index: include/gpu/GrContext.h
===================================================================
--- include/gpu/GrContext.h	(revision 10144)
+++ include/gpu/GrContext.h	(working copy)
@@ -84,6 +84,15 @@
     }
 
     /**
+     * Change the context's scratch texture reuse behavior. On some platforms

[bsalomon, 2013/07/18 18:12:08]

Do we need this function at all? Do we need anything external to GrContext to
control this?

+     * reusing scratch textures can cause the driver to ghost the texture 
+     * which, in excess, can lead to out of memory problems
+     */
+    void setReuseScratchTextures(bool reuseScratchTextures) { 
+        fReuseScratchTextures = reuseScratchTextures; 
+    }
+
+    /**
      * Abandons all GPU resources, assumes 3D API state is unknown. Call this
      * if you have lost the associated GPU context, and thus internal texture,
      * buffer, etc. references/IDs are now invalid. Should be called even when
@@ -866,6 +875,8 @@
     int                             fPMToUPMConversion;
     int                             fUPMToPMConversion;
 
+    bool                            fReuseScratchTextures;

[bsalomon, 2013/07/18 18:12:08]

Do we need this or can it just look at the GrGpu's caps?

+
     struct CleanUpData {
         PFCleanUpFunc fFunc;
         void*         fInfo;