Remove separate cache for clip mask textures

src/gpu/GrContext.cpp

Index: src/gpu/GrContext.cpp
diff --git a/src/gpu/GrContext.cpp b/src/gpu/GrContext.cpp
index 4d6b6b8d0c3e6427c680d471586f6664578f2785..065d61bb954a5d937712d6b8bf68b6aee86356d1 100644
--- a/src/gpu/GrContext.cpp
+++ b/src/gpu/GrContext.cpp
@@ -87,12 +87,6 @@ void GrContext::DrawingMgr::abandon() {
     }
 }
 
-void GrContext::DrawingMgr::purgeResources() {
-    if (fDrawTarget) {
-        fDrawTarget->purgeResources();
-    }
-}
-
 void GrContext::DrawingMgr::reset() {
     if (fDrawTarget) {
         fDrawTarget->reset();
@@ -243,8 +237,6 @@ void GrContext::resetContext(uint32_t state) {
 void GrContext::freeGpuResources() {
     this->flush();
 
-    fDrawingMgr.purgeResources();
-
     fBatchFontCache->freeAll();
     fLayerCache->freeAll();
     // a path renderer may be holding onto resources