Revert 8122 (stub call asserts) while test failures are investigated.

src/x64/regexp-macro-assembler-x64.cc

Index: src/x64/regexp-macro-assembler-x64.cc
===================================================================
--- src/x64/regexp-macro-assembler-x64.cc	(revision 8124)
+++ src/x64/regexp-macro-assembler-x64.cc	(working copy)
@@ -431,15 +431,10 @@
     // Isolate.
     __ LoadAddress(rcx, ExternalReference::isolate_address());
 #endif
+    ExternalReference compare =
+        ExternalReference::re_case_insensitive_compare_uc16(masm_.isolate());
+    __ CallCFunction(compare, num_arguments);
 
-    { // NOLINT: Can't find a way to open this scope without confusing the
-      // linter.
-      AllowExternalCallThatCantCauseGC scope(&masm_);
-      ExternalReference compare =
-          ExternalReference::re_case_insensitive_compare_uc16(masm_.isolate());
-      __ CallCFunction(compare, num_arguments);
-    }
-
     // Restore original values before reacting on result value.
     __ Move(code_object_pointer(), masm_.CodeObject());
     __ pop(backtrack_stackpointer());
@@ -713,12 +708,7 @@
   // registers we need.
   // Entry code:
   __ bind(&entry_label_);
-
-  // Tell the system that we have a stack frame.  Because the type is MANUAL, no
-  // is generated.
-  FrameScope scope(&masm_, StackFrame::MANUAL);
-
-  // Actually emit code to start a new stack frame.
+  // Start new stack frame.
   __ push(rbp);
   __ movq(rbp, rsp);
   // Save parameters and callee-save registers. Order here should correspond