Skip spinlock overhead on Android

src/gpu/batches/GrBatch.cpp

Index: src/gpu/batches/GrBatch.cpp
diff --git a/src/gpu/batches/GrBatch.cpp b/src/gpu/batches/GrBatch.cpp
index 50f94b3902fbbdbc134a0bf672359608f6283d21..6755cf94f76a788bcbdfa5a4dd0ae48a2874330f 100644
--- a/src/gpu/batches/GrBatch.cpp
+++ b/src/gpu/batches/GrBatch.cpp
@@ -23,9 +23,15 @@ namespace {
 static SkSpinlock gBatchSpinlock;
 class MemoryPoolAccessor {
 public:
-    MemoryPoolAccessor() { gBatchSpinlock.acquire(); }
 
+// We know in the Android framework there is only one GrContext.
+#if defined(SK_BUILD_FOR_ANDROID_FRAMEWORK)
+    MemoryPoolAccessor() {}
+    ~MemoryPoolAccessor() {}
+#else
+    MemoryPoolAccessor() { gBatchSpinlock.acquire(); }
     ~MemoryPoolAccessor() { gBatchSpinlock.release(); }
+#endif
 
     GrMemoryPool* pool() const {
         static GrMemoryPool gPool(16384, 16384);