Tentative implementation of string slices (hidden under the flag --string-slices).

test/cctest/test-debug.cc

Index: test/cctest/test-debug.cc
diff --git a/test/cctest/test-debug.cc b/test/cctest/test-debug.cc
index 73b84b78f067f1be724684e45c83155e813f920b..94c000dd86b9e3752f25f7380c14815b193148d2 100644
--- a/test/cctest/test-debug.cc
+++ b/test/cctest/test-debug.cc
@@ -2174,7 +2174,7 @@ TEST(ScriptBreakPointLine) {
   f = v8::Local<v8::Function>::Cast(env->Global()->Get(v8::String::New("f")));
   g = v8::Local<v8::Function>::Cast(env->Global()->Get(v8::String::New("g")));
 
-  // Chesk that a break point was hit when the script was run.
+  // Check that a break point was hit when the script was run.
   CHECK_EQ(1, break_point_hit_count);
   CHECK_EQ(0, StrLength(last_function_hit));