Remove MIPS support

runtime/vm/stack_frame_mips.h

-// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-#ifndef RUNTIME_VM_STACK_FRAME_MIPS_H_
-#define RUNTIME_VM_STACK_FRAME_MIPS_H_
-
-namespace dart {
-
-/* MIPS Dart Frame Layout
-
-               |                    | <- TOS
-Callee frame   | ...                |
-               | current RA         |    (PC of current frame)
-               | callee's PC marker |
-               +--------------------+
-Current frame  | ...               T| <- SP of current frame
-               | first local       T|
-               | caller's PP       T|
-               | CODE_REG          T|    (current frame's code object)
-               | caller's FP        | <- FP of current frame
-               | caller's RA        |    (PC of caller frame)
-               +--------------------+
-Caller frame   | last parameter     | <- SP of caller frame
-               |  ...               |
-
-               T against a slot indicates it needs to be traversed during GC.
-*/
-
-static const int kDartFrameFixedSize = 4;  // PP, FP, RA, PC marker.
-static const int kSavedPcSlotFromSp = -1;
-
-static const int kFirstObjectSlotFromFp = -1;  // Used by GC to traverse stack.
-
-static const int kFirstLocalSlotFromFp = -3;
-static const int kSavedCallerPpSlotFromFp = -2;
-static const int kPcMarkerSlotFromFp = -1;
-static const int kSavedCallerFpSlotFromFp = 0;
-static const int kSavedCallerPcSlotFromFp = 1;
-static const int kParamEndSlotFromFp = 1;  // One slot past last parameter.
-static const int kCallerSpSlotFromFp = 2;
-
-// Entry and exit frame layout.
-static const int kExitLinkSlotFromEntryFp = -24;
-COMPILE_ASSERT(kAbiPreservedCpuRegCount == 8);
-COMPILE_ASSERT(kAbiPreservedFpuRegCount == 12);
-
-}  // namespace dart
-
-#endif  // RUNTIME_VM_STACK_FRAME_MIPS_H_