Partial revert of rest parameter desugaring.

src/arm/code-stubs-arm.cc

Index: src/arm/code-stubs-arm.cc
diff --git a/src/arm/code-stubs-arm.cc b/src/arm/code-stubs-arm.cc
index 5732d0b24914286399bc8eb14cef2dd12720511f..9ab24023962945fc18327a87886d6deb6f7a6fee 100644
--- a/src/arm/code-stubs-arm.cc
+++ b/src/arm/code-stubs-arm.cc
@@ -1865,6 +1865,31 @@ void ArgumentsAccessStub::GenerateNewStrict(MacroAssembler* masm) {
 }
 
 
+void RestParamAccessStub::GenerateNew(MacroAssembler* masm) {
+  // Stack layout on entry.
+  //  sp[0] : language mode
+  //  sp[4] : index of rest parameter
+  //  sp[8] : number of parameters
+  //  sp[12] : receiver displacement
+
+  Label runtime;
+  __ ldr(r2, MemOperand(fp, StandardFrameConstants::kCallerFPOffset));
+  __ ldr(r3, MemOperand(r2, StandardFrameConstants::kContextOffset));
+  __ cmp(r3, Operand(Smi::FromInt(StackFrame::ARGUMENTS_ADAPTOR)));
+  __ b(ne, &runtime);
+
+  // Patch the arguments.length and the parameters pointer.
+  __ ldr(r1, MemOperand(r2, ArgumentsAdaptorFrameConstants::kLengthOffset));
+  __ str(r1, MemOperand(sp, 2 * kPointerSize));
+  __ add(r3, r2, Operand::PointerOffsetFromSmiKey(r1));
+  __ add(r3, r3, Operand(StandardFrameConstants::kCallerSPOffset));
+  __ str(r3, MemOperand(sp, 3 * kPointerSize));
+
+  __ bind(&runtime);
+  __ TailCallRuntime(Runtime::kNewRestParam, 4, 1);
+}
+
+
 void RegExpExecStub::Generate(MacroAssembler* masm) {
   // Just jump directly to runtime if native RegExp is not selected at compile
   // time or if regexp entry in generated code is turned off runtime switch or