Change Android retry logic - always retry 3 times.

build/android/pylib/base/base_test_sharder.py

Index: build/android/pylib/base/base_test_sharder.py
diff --git a/build/android/pylib/base/base_test_sharder.py b/build/android/pylib/base/base_test_sharder.py
index 5ff9b6209afa360d8898450feae9ec7b93d74cad..ebb4cbdf70480dc09e904e52cf067660272c8929 100644
--- a/build/android/pylib/base/base_test_sharder.py
+++ b/build/android/pylib/base/base_test_sharder.py
@@ -54,7 +54,7 @@ class BaseTestSharder(object):
     # We should differentiate between these. Otherwise, blindly retrying tests
     # might mask test/product flakiness. For type 2, we should follow the
     # general chrome best practices.
-    self.retries = len(self.attached_devices)
+    self.retries = 3

[frankf, 2013/02/14 03:42:15]

Do you have some data why the tot bot was flaky? Referring to the TODO above,
was it device or test/product flakiness? The original reason for adding retries
at all was to mitigate only device flakiness. There has been a lot of discussion
(chromium-dev and offline) regarding not masking flakiness, but either
fixing/disabling tests or fixing the product as the case may be.

[Isaac (away), 2013/02/14 06:38:50]

I agree this code would be better if we distinguished between the two.  But most
bots have 3 or more devices, so they already are doing the retries.  What I am
trying to avoid here is different behavior based on number of phones attached. 
Currently the main builder masks flakiness because it has 7 phones.

[frankf, 2013/02/14 06:43:48]

Let's define it as a constant at the top of the module.

[Isaac (away), 2013/02/14 06:53:10]

Done.

[Yaron, 2013/02/14 16:59:27]

It wasn't the bot that was flaky (it only had one device). The other bots just
masked it. Min landed https://gerrit-int.chromium.org/#/c/32469/ which should
fix one issue and 147905 can continue to track the flakiness.

     self.tests = []
     self.build_type = build_type