add back purgeResourcesNotUsedInMs() temporarily

I think this will let Android roll.

Change-Id: If6b602d66bcecd711f4340a620d78cdf27ee825f
Reviewed-on: https://skia-review.googlesource.com/84960
Reviewed-by: Mike Klein <mtklein@chromium.org>
Commit-Queue: Mike Klein <mtklein@chromium.org>

include/gpu/GrContext.h

@@ -195,6 +195,11 @@ public:
      */
     void performDeferredCleanup(std::chrono::milliseconds msNotUsed);
 
+    // Temporary compatibility API for Android.
+    void purgeResourcesNotUsedInMs(std::chrono::milliseconds msNotUsed) {
+        this->performDeferredCleanup(msNotUsed);
+    }
+
     /**
      * Purge unlocked resources from the cache until the the provided byte count has been reached
      * or we have purged all unlocked resources. The default policy is to purge in LRU order, but