Replace a dangerous function with the convenience function callers actually want.

Change-Id: Ic22dc4db36850507760a917033c254b88749b657
diff --git a/src/utils_test.cc b/src/utils_test.cc
index dd411c2..8f2b3ba 100644
--- a/src/utils_test.cc
+++ b/src/utils_test.cc
@@ -54,7 +54,7 @@
 TEST_F(UtilsTest, PrettyType) {
   EXPECT_EQ("null", PrettyType(NULL));
 
-  String* s = String::AllocFromModifiedUtf8(0, "");
+  String* s = String::AllocFromModifiedUtf8("");
   EXPECT_EQ("java.lang.String", PrettyType(s));
 
   ShortArray* a = ShortArray::Alloc(2);