Replace OS::MemCopy with OS::MemMove (just as fast but more flexible).

src/preparser-api.cc

Index: src/preparser-api.cc
diff --git a/src/preparser-api.cc b/src/preparser-api.cc
index f9c26c0e90a7b8093907a86c28801673f03c7592..462dfe2290fb562171eda39a7aeb96bd601c3543 100644
--- a/src/preparser-api.cc
+++ b/src/preparser-api.cc
@@ -100,9 +100,9 @@ class InputStreamUtf16Buffer : public Utf16CharacterStream {
         // Hit the bottom of the allocated pushback buffer.
         // Double the buffer and continue.
         uc16* new_buffer = NewArray<uc16>(pushback_buffer_backing_size_ * 2);
-        memcpy(new_buffer + pushback_buffer_backing_size_,
-               pushback_buffer_backing_,
-               pushback_buffer_backing_size_);
+        OS::MemCopy(new_buffer + pushback_buffer_backing_size_,
+                    pushback_buffer_backing_,
+                    pushback_buffer_backing_size_);
         DeleteArray(pushback_buffer_backing_);
         buffer_cursor_ = new_buffer + pushback_buffer_backing_size_;
         pushback_buffer_backing_ = pushback_buffer_ = new_buffer;