Retreive screenshots captured by tests from test devices.

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 da4da4027a1e16772665cc8ae55f3ae485aecdf1..dea8524422583c70bfbedf510016e6f8d42d21e9 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
@@ -216,8 +216,18 @@ class LocalDeviceInstrumentationTestRun(
         valgrind_tools.SetChromeTimeoutScale(
             dev, self._test_instance.timeout_scale)
 
+      @trace_event.traced

[mikecase (-- gone --), 2017/05/19 15:46:43]

Maybe add this to pull_ui_screen_captures as well if you are interested in
tracing.
pulling will probably be the thing to take more time.

[aberent, 2017/05/22 18:03:19]

Done.

+      def setup_ui_capture_dir():
+        # Make sure the UI capture directory exists and is empty by deleting
+        # and recreating it.
+        capture_dir = posixpath.join(dev.GetExternalStoragePath(),
+                                   'chromium_tests_root', 'UiCapture')

[mikecase (-- gone --), 2017/05/19 15:46:43]

nit: for indentation, I would align 'chr... with above dev...

[aberent, 2017/05/22 18:03:20]

Done.

+        if dev.PathExists(capture_dir):
+          dev.RunShellCommand(['rm', '-rf', capture_dir])
+        dev.RunShellCommand(['mkdir', capture_dir])
+
       steps += [set_debug_app, edit_shared_prefs, push_test_data,
-                create_flag_changer]
+                create_flag_changer, setup_ui_capture_dir]
       if self._env.concurrent_adb:
         reraiser_thread.RunAsync(steps)
       else:
@@ -244,6 +254,20 @@ class LocalDeviceInstrumentationTestRun(
 
       valgrind_tools.SetChromeTimeoutScale(dev, None)
 
+      if self._test_instance.ui_screenshot_dir:
+        pull_ui_screen_captures(dev)
+
+    def pull_ui_screen_captures(dev):
+      capture_dir = posixpath.join(dev.GetExternalStoragePath(),
+                                   'chromium_tests_root', 'UiCapture')

[mikecase (-- gone --), 2017/05/19 15:46:43]

I'm guessing this will have to be kept in sync with some hard-coded path in Java
code? Might be nicer to pass path in thru Instrumentation argument or via
command-line flag.

[aberent, 2017/05/22 18:03:20]

Done.

+      file_names = dev.ListDirectory(capture_dir)
+      target_path = self._test_instance.ui_screenshot_dir
+      if not os.path.exists(target_path):
+        os.makedirs(target_path)
+
+      for file_name in file_names:
+        dev.PullFile(posixpath.join(capture_dir, file_name), target_path)

[mikecase (-- gone --), 2017/05/19 15:46:43]

Even though the name doesn't make it seem like it, PullFile should pull the
entire directory if you just pass the directory to it. No need to iterate thru
the files (99% sure)

[aberent, 2017/05/22 18:03:20]

So I thought originally. The problem is that PullFile behaves like Linux cp or
mv. If the target directory exists then it creates a subdirectory with the name
of the source in the target. I could delete the target directory, but that would
delete any results of previous runs of possibly different test. If your run

adb pull /a/b /c/d

then, if d exists you will end up with /c/d/b whereas if it doesn't it will
create d and copy the contents of b into d.

+
     self._env.parallel_devices.pMap(individual_device_tear_down)
 
   def _CreateFlagChangerIfNeeded(self, device):