Ensure that SkDeferredCanvas::onCreateCompatibleDevice unrefs its temp device.

Also update my GM to use createCompatibleDevice.

Review URL: https://codereview.appspot.com/6357061

git-svn-id: http://skia.googlecode.com/svn/trunk@4450 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/utils/SkDeferredCanvas.cpp b/src/utils/SkDeferredCanvas.cpp
index 096120a..9afd580 100644
--- a/src/utils/SkDeferredCanvas.cpp
+++ b/src/utils/SkDeferredCanvas.cpp
@@ -589,9 +589,9 @@
     // Save layer usage not supported, and not required by SkDeferredCanvas.
     SkASSERT(usage != kSaveLayer_Usage);
     // Create a compatible non-deferred device.
-    SkDevice* compatibleDevice = 
-        fImmediateDevice->createCompatibleDevice(config, width, height, 
-            isOpaque);
+    SkAutoTUnref<SkDevice> compatibleDevice
+        (fImmediateDevice->createCompatibleDevice(config, width, height,
+            isOpaque));
     return SkNEW_ARGS(DeferredDevice, (compatibleDevice, fDeviceContext));
 }