remove (unused) scale parameter from measureText

BUG=skia:
R=bungeman@google.com, djsollen@google.com

Author: reed@google.com

Review URL: https://codereview.chromium.org/510433002
diff --git a/tests/PaintTest.cpp b/tests/PaintTest.cpp
index dbe7016..5106057 100644
--- a/tests/PaintTest.cpp
+++ b/tests/PaintTest.cpp
@@ -309,7 +309,7 @@
     r.setLTRB(SK_ScalarNaN, SK_ScalarNaN, SK_ScalarNaN, SK_ScalarNaN);
 
     // test that the rect was reset
-    paint.measureText("", 0, &r, 1.0f);
+    paint.measureText("", 0, &r);
     REPORTER_ASSERT(reporter, r.isEmpty());
 }