Revert of Resolve references to "this" the same way as normal variables

src/ia32/full-codegen-ia32.cc

Index: src/ia32/full-codegen-ia32.cc
diff --git a/src/ia32/full-codegen-ia32.cc b/src/ia32/full-codegen-ia32.cc
index 4c6ae2e4c4fcd8f950473e6e2e55466953404f9f..703330142e12aa3b00f90b63f42aa9f6cfc01749 100644
--- a/src/ia32/full-codegen-ia32.cc
+++ b/src/ia32/full-codegen-ia32.cc
@@ -210,9 +210,8 @@
 
     // Copy parameters into context if necessary.
     int num_parameters = info->scope()->num_parameters();
-    int first_parameter = info->scope()->has_this_declaration() ? -1 : 0;
-    for (int i = first_parameter; i < num_parameters; i++) {
-      Variable* var = (i == -1) ? scope()->receiver() : scope()->parameter(i);
+    for (int i = 0; i < num_parameters; i++) {
+      Variable* var = scope()->parameter(i);
       if (var->IsContextSlot()) {
         int parameter_offset = StandardFrameConstants::kCallerSPOffset +
             (num_parameters - 1 - i) * kPointerSize;
@@ -2960,9 +2959,7 @@
   // Push the enclosing function.
   __ push(Operand(ebp, JavaScriptFrameConstants::kFunctionOffset));
   // Push the receiver of the enclosing function.
-  Variable* this_var = scope()->LookupThis();
-  DCHECK_NOT_NULL(this_var);
-  __ push(VarOperand(this_var, ecx));
+  __ push(Operand(ebp, (2 + info_->scope()->num_parameters()) * kPointerSize));
   // Push the language mode.
   __ push(Immediate(Smi::FromInt(language_mode())));