Update V8 to version 4.1.0.21

This is a cherry-pick of all commits up to and including the
4.1.0.21 cherry-pick in Chromium.

Original commit message:

Version 4.1.0.21 (cherry-pick)

Merged 206e9136bde0f2b5ae8cb77afbb1e7833e5bd412

Unlink pages from the space page list after evacuation.

BUG=430201
LOG=N
R=jkummerow@chromium.org

Review URL: https://codereview.chromium.org/953813002

Cr-Commit-Position: refs/branch-heads/4.1@{#22}
Cr-Branched-From: 2e08d2a7aa9d65d269d8c57aba82eb38a8cb0a18-refs/heads/candidates@{#25353}

---

FPIIM-449

Change-Id: I8c23c7bbb70772b4858fe8a47b64fa97ee0d1f8c
diff --git a/src/compiler/move-optimizer.h b/src/compiler/move-optimizer.h
new file mode 100644
index 0000000..bbce686
--- /dev/null
+++ b/src/compiler/move-optimizer.h
@@ -0,0 +1,44 @@
+// 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.
+
+#ifndef V8_COMPILER_MOVE_OPTIMIZER_
+#define V8_COMPILER_MOVE_OPTIMIZER_
+
+#include "src/compiler/instruction.h"
+#include "src/zone-containers.h"
+
+namespace v8 {
+namespace internal {
+namespace compiler {
+
+class MoveOptimizer FINAL {
+ public:
+  MoveOptimizer(Zone* local_zone, InstructionSequence* code);
+  void Run();
+
+ private:
+  typedef ZoneVector<MoveOperands*> MoveOpVector;
+
+  InstructionSequence* code() const { return code_; }
+  Zone* local_zone() const { return local_zone_; }
+  Zone* code_zone() const { return code()->zone(); }
+
+  void CompressMoves(MoveOpVector* eliminated, ParallelMove* left,
+                     ParallelMove* right);
+  void FinalizeMoves(MoveOpVector* loads, MoveOpVector* new_moves,
+                     GapInstruction* gap);
+
+  Zone* const local_zone_;
+  InstructionSequence* const code_;
+  MoveOpVector temp_vector_0_;
+  MoveOpVector temp_vector_1_;
+
+  DISALLOW_COPY_AND_ASSIGN(MoveOptimizer);
+};
+
+}  // namespace compiler
+}  // namespace internal
+}  // namespace v8
+
+#endif  // V8_COMPILER_MOVE_OPTIMIZER_