Insert logcat as part of test result for android instrumentation tests.

build/android/pylib/local/device/local_device_instrumentation_test_run.py

Index: build/android/pylib/local/device/local_device_instrumentation_test_run.py
diff --git a/build/android/pylib/local/device/local_device_instrumentation_test_run.py b/build/android/pylib/local/device/local_device_instrumentation_test_run.py
index 6c00b7087dc9f5c44aeabdc2ca2abe8a17c0174c..202f612391565bee0b37a915ad25e5a257d003c7 100644
--- a/build/android/pylib/local/device/local_device_instrumentation_test_run.py
+++ b/build/android/pylib/local/device/local_device_instrumentation_test_run.py
@@ -263,8 +263,13 @@ class LocalDeviceInstrumentationTestRun(
           check_return=True)
       time_ms = lambda: int(time.time() * 1e3)
       start_ms = time_ms()
-      output = device.StartInstrumentation(
-          target, raw=True, extras=extras, timeout=timeout, retries=0)
+      output_file = '/tmp/logcat/%s' % test_name

[jbudorick, 2016/10/25 22:11:33]

Use tempfile.NamedTemporaryFile as a context manager instead of doing this:
https://docs.python.org/2/library/tempfile.html#tempfile.NamedTemporaryFile

+      with device.GetLogcatMonitor(output_file=output_file) as logmon:
+        output = device.StartInstrumentation(
+            target, raw=True, extras=extras, timeout=timeout, retries=0)
+      logmon.Close()
+      logcat = open(output_file, 'r').read()
+      os.remove(output_file)
     finally:
       device.RunShellCommand(
           ['log', '-p', 'i', '-t', _TAG, 'END %s' % test_name],
@@ -282,6 +287,8 @@ class LocalDeviceInstrumentationTestRun(
         self._test_instance.ParseAmInstrumentRawOutput(output))
     results = self._test_instance.GenerateTestResults(
         result_code, result_bundle, statuses, start_ms, duration_ms)
+    for result in results:
+      result.SetLogcat(logcat)
 
     # Update the result name if the test used flags.
     if flags: