Enable android tests on default tryjobs

PRESUBMIT.py

Index: PRESUBMIT.py
diff --git a/PRESUBMIT.py b/PRESUBMIT.py
index 1900b7eaed57d1e2240e0be548d48d4762910a4c..acd94ddf71e274d867272ecf6bcecccb87419564 100644
--- a/PRESUBMIT.py
+++ b/PRESUBMIT.py
@@ -585,10 +585,10 @@ def GetPreferredTrySlaves(project, change):
   if all(re.search('(^|[/_])win[/_.]', f) for f in files):
     return ['win_rel']
   if all(re.search('(^|[/_])android[/_.]', f) for f in files):
-    return ['android']
+    return ['android_dbg']
 
   trybots = ['win_rel', 'linux_rel', 'mac_rel', 'linux_clang:compile',
-             'linux_chromeos', 'android', 'linux_asan', 'mac_asan']
+             'linux_chromeos', 'android_dbg', 'linux_asan', 'mac_asan']
 
   # Match things like path/aura/file.cc and path/file_aura.cc.
   # Same for ash and chromeos.