Added explicit cache clearing

http://codereview.appspot.com/6492094/



git-svn-id: http://skia.googlecode.com/svn/trunk@5444 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/effects/GrTextureStripAtlas.cpp b/src/gpu/effects/GrTextureStripAtlas.cpp
index a43f9d6..86c4645 100644
--- a/src/gpu/effects/GrTextureStripAtlas.cpp
+++ b/src/gpu/effects/GrTextureStripAtlas.cpp
@@ -187,12 +187,15 @@
         fKeyTable.rewind();
     }
     GrAssert(NULL != fTexture);
+    fTexture->ref();
 }
 
 void GrTextureStripAtlas::unlockTexture() {
     GrAssert(NULL != fTexture && 0 == fLockedRows);
     fDesc.fContext->unlockTexture(fTexture);
+    fTexture->unref();
     fTexture = NULL;
+    fDesc.fContext->purgeCache();
 }
 
 void GrTextureStripAtlas::initLRU() {