Revert of Experimental support for RegExp lookbehind.

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

Index: src/regexp/mips/regexp-macro-assembler-mips.h
diff --git a/src/regexp/mips/regexp-macro-assembler-mips.h b/src/regexp/mips/regexp-macro-assembler-mips.h
index 902e2208fe87bb60e15e9d628a9fb64a9b8ac34d..da59546a79190341b4f96f82521b3656953a673e 100644
--- a/src/regexp/mips/regexp-macro-assembler-mips.h
+++ b/src/regexp/mips/regexp-macro-assembler-mips.h
@@ -33,11 +33,9 @@
   // A "greedy loop" is a loop that is both greedy and with a simple
   // body. It has a particularly simple implementation.
   virtual void CheckGreedyLoop(Label* on_tos_equals_current_position);
-  virtual void CheckNotAtStart(int cp_offset, Label* on_not_at_start);
-  virtual void CheckNotBackReference(int start_reg, bool read_backward,
-                                     Label* on_no_match);
+  virtual void CheckNotAtStart(Label* on_not_at_start);
+  virtual void CheckNotBackReference(int start_reg, Label* on_no_match);
   virtual void CheckNotBackReferenceIgnoreCase(int start_reg,
-                                               bool read_backward,
                                                Label* on_no_match);
   virtual void CheckNotCharacter(uint32_t c, Label* on_not_equal);
   virtual void CheckNotCharacterAfterAnd(uint32_t c,
@@ -122,9 +120,9 @@
   // When adding local variables remember to push space for them in
   // the frame in GetCode.
   static const int kSuccessfulCaptures = kInputString - kPointerSize;
-  static const int kStringStartMinusOne = kSuccessfulCaptures - kPointerSize;
+  static const int kInputStartMinusOne = kSuccessfulCaptures - kPointerSize;
   // First register address. Following registers are below it on the stack.
-  static const int kRegisterZero = kStringStartMinusOne - kPointerSize;
+  static const int kRegisterZero = kInputStartMinusOne - kPointerSize;
 
   // Initial size of code buffer.
   static const size_t kRegExpCodeSize = 1024;