Add asserts and state tracking to ensure that we do not call

src/code-stubs.h

Index: src/code-stubs.h
===================================================================
--- src/code-stubs.h	(revision 8110)
+++ src/code-stubs.h	(working copy)
@@ -75,7 +75,7 @@
   V(KeyedLoadExternalArray)              \
   V(KeyedStoreExternalArray)             \
   V(DebuggerStatement)                   \
-  V(StringDictionaryNegativeLookup)
+  V(StringDictionaryLookup)
 
 // List of code stubs only used on ARM platforms.
 #ifdef V8_TARGET_ARCH_ARM
@@ -144,6 +144,13 @@
 
   virtual ~CodeStub() {}
 
+  // See comment above, where Instanceof is defined.
+  virtual bool CompilingCallsToThisStubIsGCSafe() {
+    return MajorKey() <= Instanceof;
+  }
+
+  virtual bool SometimesSetsUpAFrame() { return true; }
+
  protected:
   static const int kMajorBits = 6;
   static const int kMinorBits = kBitsPerInt - kSmiTagSize - kMajorBits;
@@ -200,9 +207,6 @@
            MajorKeyBits::encode(MajorKey());
   }
 
-  // See comment above, where Instanceof is defined.
-  bool AllowsStubCalls() { return MajorKey() <= Instanceof; }
-
   class MajorKeyBits: public BitField<uint32_t, 0, kMajorBits> {};
   class MinorKeyBits: public BitField<uint32_t, kMajorBits, kMinorBits> {};
 
@@ -575,6 +579,11 @@
   void Generate(MacroAssembler* masm);
   void SaveDoubles() { save_doubles_ = true; }
 
+  // The version of this stub that doesn't save doubles is generated ahead of
+  // time, so it's OK to call it from other stubs that can't cope with GC during
+  // their code generation.
+  virtual bool CompilingCallsToThisStubIsGCSafe() { return !save_doubles_; }
+
  private:
   void GenerateCore(MacroAssembler* masm,
                     Label* throw_normal_exception,