Update V8 to r5425 as required by WebKit r67178

Change-Id: Ic338e7242d33e5a024bd5978f4a5a3a681af4ebd
diff --git a/src/arm/macro-assembler-arm.h b/src/arm/macro-assembler-arm.h
index 207ee5c..febd87e 100644
--- a/src/arm/macro-assembler-arm.h
+++ b/src/arm/macro-assembler-arm.h
@@ -504,6 +504,15 @@
                               Register scratch1,
                               SwVfpRegister scratch2);
 
+  // Convert the HeapNumber pointed to by source to a 32bits signed integer
+  // dest. If the HeapNumber does not fit into a 32bits signed integer branch
+  // to not_int32 label.
+  void ConvertToInt32(Register source,
+                      Register dest,
+                      Register scratch,
+                      Register scratch2,
+                      Label *not_int32);
+
   // Count leading zeros in a 32 bit word.  On ARM5 and later it uses the clz
   // instruction.  On pre-ARM5 hardware this routine gives the wrong answer
   // for 0 (31 instead of 32).  Source and scratch can be the same in which case