Resubmit issue 2221103002 to fix the iOS build by declaring the flag in

tools/flags/SkCommonFlags.cpp

Index: tools/flags/SkCommonFlags.cpp
diff --git a/tools/flags/SkCommonFlags.cpp b/tools/flags/SkCommonFlags.cpp
index bf2bde0426d929de8f56cac90a3a4664f5bdd030..d0cdf315df43c0ca16921f21998df0ad15bc28a6 100644
--- a/tools/flags/SkCommonFlags.cpp
+++ b/tools/flags/SkCommonFlags.cpp
@@ -65,6 +65,8 @@ DEFINE_string(properties, "",
               "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");
+
 bool CollectImages(SkCommandLineFlags::StringArray images, SkTArray<SkString>* output) {
     SkASSERT(output);