Windows build fix.

TBR=ulan@chromium.org

Review URL: https://codereview.chromium.org/189093009

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@19721 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/assembler.cc

@@ -1622,7 +1622,8 @@ MultiplierAndShift::MultiplierAndShift(int32_t d) {
     }
     delta = ad - r2;
   } while (q1 < delta || (q1 == delta && r1 == 0));
-  multiplier_ = (d < 0) ? -(q2 + 1) : (q2 + 1);
+  int32_t mul = static_cast<int32_t>(q2 + 1);
+  multiplier_ = (d < 0) ? -mul : mul;
   shift_ = p - 32;
 }