Extract hardcoded error strings into a single place and replace them with enum.

src/ia32/deoptimizer-ia32.cc

Index: src/ia32/deoptimizer-ia32.cc
diff --git a/src/ia32/deoptimizer-ia32.cc b/src/ia32/deoptimizer-ia32.cc
index 48968064aa357f39feaa0c21c260d3bd71e49710..a9bd8c50b72b642f57e4b77882134ad4b3524908 100644
--- a/src/ia32/deoptimizer-ia32.cc
+++ b/src/ia32/deoptimizer-ia32.cc
@@ -625,7 +625,7 @@ void Deoptimizer::EntryGenerator::Generate() {
     __ pop(ecx);
     if (FLAG_debug_code) {
       __ cmp(ecx, Immediate(kAlignmentZapValue));
-      __ Assert(equal, "alignment marker expected");
+      __ Assert(equal, kAlignmentMarkerExpected);
     }
     __ bind(&no_padding);
   } else {