tast: Disable android tests on master-arc-dev.

master-arc-dev is not stable enough to run tests.
Temporarily disable it.
To run some ARC tests on master-arc-dev, too,
introduces android_full.

BUG=chromium:936337
TEST=Ran on DUT.
CQ-DEPEND=CL:1494046

Change-Id: Id0bc7be8e3a2dddc787297d51e7827315b10c8dc
Reviewed-on: https://chromium-review.googlesource.com/1494114
Commit-Ready: ChromeOS CL Exonerator Bot <[email protected]>
Tested-by: Hidehiko Abe <[email protected]>
Reviewed-by: Hidehiko Abe <[email protected]>
diff --git a/docs/test_dependencies.md b/docs/test_dependencies.md
index 0da6008..0ba459f 100644
--- a/docs/test_dependencies.md
+++ b/docs/test_dependencies.md
@@ -14,8 +14,9 @@
 The following software features are defined:
 
 *   `amd64` - The [amd64] processor architecture.
-*   `android` - The ability to [run Android apps]. Any version of Android can be
-    used.
+*   `android` - The ability to [run Android apps]. Any production version of
+    Android (i.e. ones except `master-arc-dev`) can be used.
+*   `android_all` - in addition to `android`, runs on `master-arc-dev`, too.
 *   `android_p` - The ability to [run Android apps] that require Android P or
     later.
 *   `arc_camera3` - The [Camera HAL3] interface in Android.