Change FLAGS_analyticAA's default to true

BUG=skia:

Change-Id: I1abf2284ed9dfaa69110c4fe86325c8e4ee43317
Reviewed-on: https://skia-review.googlesource.com/5767
Reviewed-by: Derek Sollenberger <djsollen@google.com>
Commit-Queue: Yuqian Li <liyuqian@google.com>
diff --git a/tools/flags/SkCommonFlags.cpp b/tools/flags/SkCommonFlags.cpp
index 02d8054..52a5388 100644
--- a/tools/flags/SkCommonFlags.cpp
+++ b/tools/flags/SkCommonFlags.cpp
@@ -66,7 +66,7 @@
               "Space-separated key/value pairs to add to JSON identifying this run.");
 DEFINE_bool2(pre_log, p, false, "Log before running each test. May be incomprehensible when threading");
 
-DEFINE_bool(analyticAA, false, "Analytic Anati-Alias");
+DEFINE_bool(analyticAA, true, "If false, disable analytic anti-aliasing");
 
 bool CollectImages(SkCommandLineFlags::StringArray images, SkTArray<SkString>* output) {
     SkASSERT(output);