MIPS: replace RegExpCEntryStub with DirectCEntryStub.

src/mips/regexp-macro-assembler-mips.h

Index: src/mips/regexp-macro-assembler-mips.h
diff --git a/src/mips/regexp-macro-assembler-mips.h b/src/mips/regexp-macro-assembler-mips.h
index 86ae4d45eebe763142acdb04028d5141b45331f9..063582c64851dff1162b558c83d7f8eb77f5d94e 100644
--- a/src/mips/regexp-macro-assembler-mips.h
+++ b/src/mips/regexp-macro-assembler-mips.h
@@ -217,14 +217,6 @@ class RegExpMacroAssemblerMIPS: public NativeRegExpMacroAssembler {
   // and increments it by a word size.
   inline void Pop(Register target);
 
-  // Calls a C function and cleans up the frame alignment done by
-  // by FrameAlign. The called function *is* allowed to trigger a garbage
-  // collection, but may not take more than four arguments (no arguments
-  // passed on the stack), and the first argument will be a pointer to the
-  // return address.
-  inline void CallCFunctionUsingStub(ExternalReference function,
-                                     int num_arguments);
-
   Isolate* isolate() const { return masm_->isolate(); }
 
   MacroAssembler* masm_;