Add fine-grained diff implementation to LiveEdit engine.

src/liveedit.h

Index: src/liveedit.h
diff --git a/src/liveedit.h b/src/liveedit.h
index 3632180f9922f1fc8a7cabbdac80b4b62e6b3fa3..5f2c99c3d737bf78d7932e4e090e1fe9e77fd8a1 100644
--- a/src/liveedit.h
+++ b/src/liveedit.h
@@ -126,10 +126,11 @@ class LiveEdit : AllStatic {
     FUNCTION_REPLACED_ON_ACTIVE_STACK = 5
   };
 
-  // Compares 2 strings line-by-line and returns diff in form of array of
-  // triplets (pos1, pos1_end, pos2_end) describing list of diff chunks.
-  static Handle<JSArray> CompareStringsLinewise(Handle<String> s1,
-                                                Handle<String> s2);
+  // Compares 2 strings line-by-line, then token-wise and returns diff in form
+  // of array of triplets (pos1, pos1_end, pos2_end) describing list
+  // of diff chunks.
+  static Handle<JSArray> CompareStrings(Handle<String> s1,
+                                        Handle<String> s2);
 };