MIPS: Introduce LanguageMode, drop StrictMode.

src/compiler/mips64/code-generator-mips64.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/compiler/code-generator.h"
 #include "src/compiler/code-generator-impl.h"
 #include "src/compiler/gap-resolver.h"
 #include "src/compiler/node-matchers.h"
 #include "src/mips/macro-assembler-mips.h"
 #include "src/scopes.h"
@@ skipping 1043 matching lines @@
   } else if (descriptor->IsJSFunctionCall()) {
     CompilationInfo* info = this->info();
     __ Prologue(info->IsCodePreAgingActive());
     frame()->SetRegisterSaveAreaSize(
         StandardFrameConstants::kFixedFrameSizeFromFp);
 
     // Sloppy mode functions and builtins need to replace the receiver with the
     // global proxy when called as functions (without an explicit receiver
     // object).
     // TODO(mstarzinger/verwaest): Should this be moved back into the CallIC?
-    if (info->strict_mode() == SLOPPY && !info->is_native()) {
+    if (is_sloppy(info->language_mode()) && !info->is_native()) {
       Label ok;
       // +2 for return address and saved frame pointer.
       int receiver_slot = info->scope()->num_parameters() + 2;
       __ ld(a2, MemOperand(fp, receiver_slot * kPointerSize));
       __ LoadRoot(at, Heap::kUndefinedValueRootIndex);
       __ Branch(&ok, ne, a2, Operand(at));
 
       __ ld(a2, GlobalObjectOperand());
       __ ld(a2, FieldMemOperand(a2, GlobalObject::kGlobalProxyOffset));
       __ sd(a2, MemOperand(fp, receiver_slot * kPointerSize));
@@ skipping 244 matching lines @@
     }
   }
   MarkLazyDeoptSite();
 }
 
 #undef __
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8