Oilpan: Remove Heap::getStats

Source/platform/heap/Heap.h

Index: Source/platform/heap/Heap.h
diff --git a/Source/platform/heap/Heap.h b/Source/platform/heap/Heap.h
index 6c4781dec79f3c8180ed80eb1a2ec8bec88f4669..402861bb91a2f2ea1d2ba1d1358be30af2810831 100644
--- a/Source/platform/heap/Heap.h
+++ b/Source/platform/heap/Heap.h
@@ -963,11 +963,6 @@ public:
     static String createBacktraceString();
 #endif
 
-    // Collect heap stats for all threads attached to the Blink
-    // garbage collector. Should only be called during garbage
-    // collection where threads are known to be at safe points.
-    static void getStats(HeapStats*);
-
     static void getStatsForTesting(HeapStats*);
 
     static void getHeapSpaceSize(uint64_t*, uint64_t*);