Update V8 to r7079 as required by WebKit r80534.

Change-Id: I487c152e485d5a40b68997d7c0d2f1fba5da0834
diff --git a/src/arm/constants-arm.h b/src/arm/constants-arm.h
index 7ac38ed..e6033a8 100644
--- a/src/arm/constants-arm.h
+++ b/src/arm/constants-arm.h
@@ -385,7 +385,10 @@
   kDefaultRoundToZero = 1
 };
 
+// This mask does not include the "inexact" or "input denormal" cumulative
+// exceptions flags, because we usually don't want to check for it.
 static const uint32_t kVFPExceptionMask = 0xf;
+static const uint32_t kVFPInexactExceptionBit = 1 << 4;
 static const uint32_t kVFPFlushToZeroMask = 1 << 24;
 static const uint32_t kVFPInvalidExceptionBit = 1;
 
@@ -411,6 +414,11 @@
 
 static const uint32_t kVFPRoundingModeMask = 3 << 22;
 
+enum CheckForInexactConversion {
+  kCheckForInexactConversion,
+  kDontCheckForInexactConversion
+};
+
 // -----------------------------------------------------------------------------
 // Hints.