Fix a missing synchronized block in LruCache.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=165650311

library/src/main/java/com/bumptech/glide/util/LruCache.java

@@ -58,7 +58,7 @@ public class LruCache<T, Y> {
   /**
    * Returns the number of entries stored in cache.
    */
-  protected int getCount() {
+  protected synchronized int getCount() {
     return cache.size();
   }