Fix bug that happens when the first non-ASCII character of a literal is at a power-of-two position.

src/scanner-base.h

Index: src/scanner-base.h
diff --git a/src/scanner-base.h b/src/scanner-base.h
index e773586d044ef047e5a0a88dba2f0754e3a6a412..b668df5046dae63903c4a2fd6445336235a24024 100644
--- a/src/scanner-base.h
+++ b/src/scanner-base.h
@@ -214,7 +214,9 @@ class LiteralBuffer {
     ASSERT(is_ascii_);
     Vector<byte> new_store;
     int new_content_size = position_ * kUC16Size;
-    if (new_content_size > backing_store_.length()) {
+    if (new_content_size >= backing_store_.length()) {
+      // Ensure room for all currently read characters as UC16 as well
+      // as the character about to be stored.
       new_store = Vector<byte>::New(NewCapacity(new_content_size));
     } else {
       new_store = backing_store_;