Implement tracking and optimizations of packed arrays.

src/arm/stub-cache-arm.cc

Index: src/arm/stub-cache-arm.cc
diff --git a/src/arm/stub-cache-arm.cc b/src/arm/stub-cache-arm.cc
index 1cd0e655ee4c118d6c46e9072d1c4517a66c7624..5d131e6fba23cc850859395552b131c66a6e9ab3 100644
--- a/src/arm/stub-cache-arm.cc
+++ b/src/arm/stub-cache-arm.cc
@@ -1583,7 +1583,7 @@ Handle<Code> CallStubCompiler::CompileArrayPushCall(
                                                r7,
                                                &call_builtin);
         __ mov(r2, receiver);
-        ElementsTransitionGenerator::GenerateSmiOnlyToObject(masm());
+        ElementsTransitionGenerator::GenerateMapChangeElementTransition(masm());
         __ bind(&fast_object);
       } else {
         __ CheckFastObjectElements(r3, r3, &call_builtin);
@@ -4246,7 +4246,7 @@ void KeyedStoreStubCompiler::GenerateStoreFastElement(
               DONT_DO_SMI_CHECK);
 
   __ bind(&finish_store);
-  if (elements_kind == FAST_SMI_ONLY_ELEMENTS) {
+  if (IsFastSmiElementsKind(elements_kind)) {
     __ add(scratch,
            elements_reg,
            Operand(FixedArray::kHeaderSize - kHeapObjectTag));
@@ -4256,7 +4256,7 @@ void KeyedStoreStubCompiler::GenerateStoreFastElement(
            Operand(key_reg, LSL, kPointerSizeLog2 - kSmiTagSize));
     __ str(value_reg, MemOperand(scratch));
   } else {
-    ASSERT(elements_kind == FAST_ELEMENTS);
+    ASSERT(IsFastObjectElementsKind(elements_kind));
     __ add(scratch,
            elements_reg,
            Operand(FixedArray::kHeaderSize - kHeapObjectTag));