V8ScriptValueSerializer: Use PartitionAlloc for the buffer, and avoid copying it into a String.

third_party/WebKit/Source/wtf/allocator/Partitions.h

Index: third_party/WebKit/Source/wtf/allocator/Partitions.h
diff --git a/third_party/WebKit/Source/wtf/allocator/Partitions.h b/third_party/WebKit/Source/wtf/allocator/Partitions.h
index 506bb73a7700419163e7e4729d12d061297662bc..8fd74a3f73dc8bc2b0495b9a52a4108cdeff02fc 100644
--- a/third_party/WebKit/Source/wtf/allocator/Partitions.h
+++ b/third_party/WebKit/Source/wtf/allocator/Partitions.h
@@ -90,6 +90,11 @@ class WTF_EXPORT Partitions {
   ALWAYS_INLINE static void* bufferMalloc(size_t n, const char* typeName) {
     return partitionAllocGeneric(bufferPartition(), n, typeName);
   }
+  ALWAYS_INLINE static void* bufferRealloc(void* p,
+                                           size_t n,
+                                           const char* typeName) {
+    return partitionReallocGeneric(bufferPartition(), p, n, typeName);
+  }
   ALWAYS_INLINE static void bufferFree(void* p) {
     partitionFreeGeneric(bufferPartition(), p);
   }