Add negative lookups to polymorphic loads in Crankshaft.

src/arm/macro-assembler-arm.h

Index: src/arm/macro-assembler-arm.h
===================================================================
--- src/arm/macro-assembler-arm.h	(revision 11774)
+++ src/arm/macro-assembler-arm.h	(working copy)
@@ -831,6 +831,13 @@
                   Label* early_success,
                   CompareMapMode mode = REQUIRE_EXACT_MAP);
 
+  // As above, but the map of the object is already loaded into the register
+  // which is preserved by the code generated.
+  void CompareMap(Register obj_map,
+                  Handle<Map> map,
+                  Label* early_success,
+                  CompareMapMode mode = REQUIRE_EXACT_MAP);
+
   // Check if the map of an object is equal to a specified map and branch to
   // label if not. Skip the smi check if not required (object is known to be a
   // heap object). If mode is ALLOW_ELEMENT_TRANSITION_MAPS, then also match