Update Android test instructions.

docs/android_test_instructions.md

 # Android Test Instructions
 
 Device Setup Tests are runnable on physical devices or emulators. See the
 instructions below for setting up either a physical device or an emulator.
 
 [TOC]
 
 ## Physical Device Setup **ADB Debugging**
 
 In order to allow the ADB to connect to the device, you must enable USB
@@ skipping 33 matching lines @@
 behavior._ This can interfere with the test runner. To disable this dialog, run:
 `adb shell settings put global package_verifier_enable 0`
 
 ## Emulator Setup
 
 ### Option 1:
 
 Use an emulator (i.e. Android Virtual Device, AVD): Enabling Intel's
 Virtualizaton support provides the fastest, most reliable emulator configuration
 available (i.e. x86 emulator with GPU acceleration and KVM support).
+Remember to build with `target_arch=ia32` for x86. Otherwise installing the APKs
+will fail with `INSTALL_FAILED_NO_MATCHING_ABIS`.
 
 1.  Enable Intel Virtualization support in the BIOS.
 
 2.  Set up your environment:
 
     ```shell
     . build/android/envsetup.sh
     ```
 
 3.  Install emulator deps:
 
     ```shell
-    build/android/install_emulator_deps.py --api-level=19
+    build/android/install_emulator_deps.py --api-level=23
     ```
 
     This script will download Android SDK and place it a directory called
     android\_tools in the same parent directory as your chromium checkout. It
     will also download the system-images for the emulators (i.e. arm and x86).
     Note that this is a different SDK download than the Android SDK in the
     chromium source checkout (i.e. src/third\_party/android\_emulator\_sdk).
 
 4.  Run the avd.py script. To start up _num_ emulators use -n. For non-x86 use
     --abi.
 
     ```shell
-    build/android/avd.py --api-level=19
+    build/android/avd.py --api-level=23
     ```
 
     This script will attempt to use GPU emulation, so you must be running the
     emulators in an environment with hardware rendering available. See
     `avd.py --help` for more details.
 
 ### Option 2:
 
 Alternatively, you can create an run your own emulator using the tools provided
 by the Android SDK. When doing so, be sure to enable GPU emulation in hardware
@@ skipping 41 matching lines @@
 `--output-directory=out_android/Debug`.
 
 ## INSTALL\_FAILED\_CONTAINER\_ERROR or INSTALL\_FAILED\_INSUFFICIENT\_STORAGE
 
 If you see this error when test\_runner.py is attempting to deploy the test
 binaries to the AVD emulator, you may need to resize your userdata partition
 with the following commands:
 
 ```shell
 # Resize userdata partition to be 1G
-resize2fs android_emulator_sdk/sdk/system-images/android-19/x86/userdata.img 1G
+resize2fs android_emulator_sdk/sdk/system-images/android-23/x86/userdata.img 1G
 
 # Set filesystem parameter to continue on errors; Android doesn't like some
 # things e2fsprogs does.
-tune2fs -e continue android_emulator_sdk/sdk/system-images/android-19/x86/userdata.img
+tune2fs -e continue android_emulator_sdk/sdk/system-images/android-23/x86/userdata.img
 ```
 
 ## Symbolizing Crashes
 
 Crash stacks are logged and can be viewed using adb logcat. To symbolize the
 traces, pipe the output through
 `third_party/android_platform/development/scripts/stack`. If you build in an
 output directory other than "out", pass
 `--chrome-symbols-dir=out_directory/{Debug,Release}/lib` to the script as well.
 
@@ skipping 130 matching lines @@
 See
 https://sites.google.com/a/chromium.org/dev/developers/testing/webkit-layout-tests
 
 ## Running GPU tests
 
 (e.g. the "Android Debug (Nexus 7)" bot on the chromium.gpu waterfall)
 
 See http://www.chromium.org/developers/testing/gpu-testing for details. Use
 --browser=android-content-shell. Examine the stdio from the test invocation on
 the bots to see arguments to pass to src/content/test/gpu/run\_gpu\_test.py.