Unify DrawProfiler/JankStats

Bug: 20822400

Change-Id: I24345c3120440bfce14e8cbe7e880b39f10b744a
diff --git a/libs/hwui/utils/RingBuffer.h b/libs/hwui/utils/RingBuffer.h
index fc9aec0..6d0a06b 100644
--- a/libs/hwui/utils/RingBuffer.h
+++ b/libs/hwui/utils/RingBuffer.h
@@ -31,7 +31,7 @@
     RingBuffer() {}
     ~RingBuffer() {}
 
-    size_t capacity() { return SIZE; }
+    constexpr size_t capacity() { return SIZE; }
     size_t size() { return mCount; }
 
     T& next() {