Introduce code flushing of RegExp code.

src/factory.cc

Index: src/factory.cc
===================================================================
--- src/factory.cc	(revision 8501)
+++ src/factory.cc	(working copy)
@@ -1221,12 +1221,14 @@
                                     JSRegExp::Flags flags,
                                     int capture_count) {
   Handle<FixedArray> store = NewFixedArray(JSRegExp::kIrregexpDataSize);
-
+  Smi* uninitialized = Smi::FromInt(JSRegExp::kUninitializedValue);
   store->set(JSRegExp::kTagIndex, Smi::FromInt(type));
   store->set(JSRegExp::kSourceIndex, *source);
   store->set(JSRegExp::kFlagsIndex, Smi::FromInt(flags.value()));
-  store->set(JSRegExp::kIrregexpASCIICodeIndex, HEAP->the_hole_value());
-  store->set(JSRegExp::kIrregexpUC16CodeIndex, HEAP->the_hole_value());
+  store->set(JSRegExp::kIrregexpASCIICodeIndex, uninitialized);
+  store->set(JSRegExp::kIrregexpUC16CodeIndex, uninitialized);
+  store->set(JSRegExp::kIrregexpASCIICodeSavedIndex, uninitialized);
+  store->set(JSRegExp::kIrregexpUC16CodeSavedIndex, uninitialized);
   store->set(JSRegExp::kIrregexpMaxRegisterCountIndex, Smi::FromInt(0));
   store->set(JSRegExp::kIrregexpCaptureCountIndex,
              Smi::FromInt(capture_count));