Remove the barely used macro assemblers after merging their contents to the base

runtime/vm/assembler_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 VM_ASSEMBLER_MIPS_H_
 #define VM_ASSEMBLER_MIPS_H_
 
 #ifndef VM_ASSEMBLER_H_
 #error Do not include assembler_mips.h directly; use assembler.h instead.
 #endif
@@ skipping 133 matching lines @@
     return *pointer_offsets_;
   }
   const GrowableObjectArray& object_pool() const {
     UNIMPLEMENTED();
     return object_pool_;
   }
   void FinalizeInstructions(const MemoryRegion& region) {
     UNIMPLEMENTED();
   }
 
+  // Set up a Dart frame on entry with a frame pointer and PC information to
+  // enable easy access to the RawInstruction object of code corresponding
+  // to this frame.
+  void EnterDartFrame(intptr_t frame_size) {
+    UNIMPLEMENTED();
+  }
+
+  // Set up a stub frame so that the stack traversal code can easily identify
+  // a stub frame.
+  void EnterStubFrame() {
+    UNIMPLEMENTED();
+  }
+
+  // Instruction pattern from entrypoint is used in dart frame prologs
+  // to set up the frame and save a PC which can be used to figure out the
+  // RawInstruction object corresponding to the code running in the frame.
+  static const intptr_t kOffsetOfSavedPCfromEntrypoint = -1;  // UNIMPLEMENTED.
+
+  // Inlined allocation of an instance of class 'cls', code has no runtime
+  // calls. Jump to 'failure' if the instance cannot be allocated here.
+  // Allocated instance is returned in 'instance_reg'.
+  // Only the tags field of the object is initialized.
+  void TryAllocate(const Class& cls,
+                   Label* failure,
+                   bool near_jump,
+                   Register instance_reg) {
+    UNIMPLEMENTED();
+  }
+
   // Debugging and bringup support.
   void Stop(const char* message) { UNIMPLEMENTED(); }
   void Unimplemented(const char* message);
   void Untested(const char* message);
   void Unreachable(const char* message);
 
   static void InitializeMemoryWithBreakpoints(uword data, int length) {
     UNIMPLEMENTED();
   }
 
@@ skipping 34 matching lines @@
 
   GrowableArray<CodeComment*> comments_;
 
   DISALLOW_ALLOCATION();
   DISALLOW_COPY_AND_ASSIGN(Assembler);
 };
 
 }  // namespace dart
 
 #endif  // VM_ASSEMBLER_MIPS_H_