Update Android Studio code style instructions.

docs/android_studio.md

 # Android Studio
 
 [TOC]
 
 ## Usage
 
 Make sure you have followed
 [android build instructions](android_build_instructions.md) already.
 
 ```shell
@@ skipping 74 matching lines @@
 
 ## Android Studio Tips
 
 * Configuration instructions can be found
   [here](http://tools.android.com/tech-docs/configuration). One suggestions:
     * Launch it with more RAM:
       `STUDIO_VM_OPTIONS=-Xmx2048m /opt/android-studio-stable/bin/studio-launcher.sh`
 * If you ever need to reset it: `rm -r ~/.AndroidStudio*/`
 * Import Android style settings:
     * Help -> Find Action -> "Code Style" (settings) -> Java ->
-      Manage -> Import
+      Manage -> Import -> select "Intellij IDEA code style XML" -> OK
         * Select `tools/android/android_studio/ChromiumStyle.xml`
 * Turn on automatic import:
     * Help -> Find Action -> "Auto Import"
         * Tick all the boxes under "Java" and change the dropdown to "All".
 * Turn on documentation on mouse hover:
     * Help -> Find Action -> "Show quick documentation on mouse move"
 * Turn on line numbers:
     * Help -> Find Action -> "Show line numbers"
 
 ### Useful Shortcuts
@@ skipping 39 matching lines @@
 [here](/docs/android_debugging_instructions.md#Android-Studio)).
 * Import resolution and refactoring across all modules.
 * Correct lint and AndroidManifest when only one target is specified.
 
 ### What doesn't work (yet) ([crbug](https://bugs.chromium.org/p/chromium/issues/detail?id=620034))
 
 * Gradle being aware of assets.
 * Layout editor.
 * Add support for native code editing.
 * Make the "Make Project" button work correctly.