Remove scratch register requirement from LoadInstanceDescriptors on arm and mips.

src/mips/lithium-mips.h

Index: src/mips/lithium-mips.h
diff --git a/src/mips/lithium-mips.h b/src/mips/lithium-mips.h
index 939fc676b29d602ba44820b0736d497c65510628..3a9aa7accfbe4c2ee8c16561adb39dfa1b877437 100644
--- a/src/mips/lithium-mips.h
+++ b/src/mips/lithium-mips.h
@@ -2379,15 +2379,13 @@ class LForInPrepareMap: public LTemplateInstruction<1, 1, 0> {
 };
 
 
-class LForInCacheArray: public LTemplateInstruction<1, 1, 1> {
+class LForInCacheArray: public LTemplateInstruction<1, 1, 0> {
  public:
-  explicit LForInCacheArray(LOperand* map, LOperand* scratch) {
+  explicit LForInCacheArray(LOperand* map) {
     inputs_[0] = map;
-    temps_[0] = scratch;
   }
 
   LOperand* map() { return inputs_[0]; }
-  LOperand* scratch() { return temps_[0]; }
 
   DECLARE_CONCRETE_INSTRUCTION(ForInCacheArray, "for-in-cache-array")