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

src/ia32/regexp-macro-assembler-ia32.cc

Index: src/ia32/regexp-macro-assembler-ia32.cc
===================================================================
--- src/ia32/regexp-macro-assembler-ia32.cc	(revision 8110)
+++ src/ia32/regexp-macro-assembler-ia32.cc	(working copy)
@@ -396,9 +396,14 @@
     __ add(edx, Operand(esi));
     __ mov(Operand(esp, 0 * kPointerSize), edx);
 
-    ExternalReference compare =
-        ExternalReference::re_case_insensitive_compare_uc16(masm_->isolate());
-    __ CallCFunction(compare, argument_count);
+    {
+      // The compare function can't cause a GC.  Tell the system that it is OK
+      // to call into C++ without having a stack frame in place.
+      FrameScope scope(masm_, StackFrame::NONE);
+      ExternalReference compare =
+          ExternalReference::re_case_insensitive_compare_uc16(masm_->isolate());
+      __ CallCFunction(compare, argument_count);
+    }
     // Pop original values before reacting on result value.
     __ pop(ebx);
     __ pop(backtrack_stackpointer());
@@ -668,7 +673,12 @@
 
   // Entry code:
   __ bind(&entry_label_);
-  // Start new stack frame.
+
+  // Tell the system that we have a stack frame.  Because the type is NONE, no
+  // is generated.
+  FrameScope scope(masm_, StackFrame::NONE);
+
+  // Actually emit code to start a new stack frame.
   __ push(ebp);
   __ mov(ebp, esp);
   // Save callee-save registers. Order here should correspond to order of