Fix asserts and GC unsafeness in stub generation, bug=1689.

src/isolate.h

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 861 matching lines @@
   StringInputBuffer* objects_string_compare_buffer_b() {
     return &objects_string_compare_buffer_b_;
   }
 
   StaticResource<StringInputBuffer>* objects_string_input_buffer() {
     return &objects_string_input_buffer_;
   }
 
   RuntimeState* runtime_state() { return &runtime_state_; }
 
+  void set_fp_stubs_generated(bool value) {
+    fp_stubs_generated_ = value;
+  }
+
+  bool fp_stubs_generated() { return fp_stubs_generated_; }
+
   StaticResource<SafeStringInputBuffer>* compiler_safe_string_input_buffer() {
     return &compiler_safe_string_input_buffer_;
   }
 
   Builtins* builtins() { return &builtins_; }
 
   unibrow::Mapping<unibrow::Ecma262Canonicalize>*
       regexp_macro_assembler_canonicalize() {
     return &regexp_macro_assembler_canonicalize_;
   }
@@ skipping 237 matching lines @@
   Zone zone_;
   PreallocatedStorage in_use_list_;
   PreallocatedStorage free_list_;
   bool preallocated_storage_preallocated_;
   PcToCodeCache* pc_to_code_cache_;
   StringInputBuffer* write_input_buffer_;
   GlobalHandles* global_handles_;
   ContextSwitcher* context_switcher_;
   ThreadManager* thread_manager_;
   RuntimeState runtime_state_;
+  bool fp_stubs_generated_;
   StaticResource<SafeStringInputBuffer> compiler_safe_string_input_buffer_;
   Builtins builtins_;
   StringTracker* string_tracker_;
   unibrow::Mapping<unibrow::Ecma262UnCanonicalize> jsregexp_uncanonicalize_;
   unibrow::Mapping<unibrow::CanonicalizationRange> jsregexp_canonrange_;
   StringInputBuffer objects_string_compare_buffer_a_;
   StringInputBuffer objects_string_compare_buffer_b_;
   StaticResource<StringInputBuffer> objects_string_input_buffer_;
   unibrow::Mapping<unibrow::Ecma262Canonicalize>
       regexp_macro_assembler_canonicalize_;
@@ skipping 204 matching lines @@
 
 // Mark the global context with out of memory.
 inline void Context::mark_out_of_memory() {
   global_context()->set_out_of_memory(HEAP->true_value());
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_ISOLATE_H_