Android: Upgrade to Android Studio 2.3

Support Clank development with the next version of Android Studio.

BUG=700438

Review-Url: https://codereview.chromium.org/2797703004
Cr-Original-Commit-Position: refs/heads/master@{#462050}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: fdea62ce258c0abf7327f1081af9d964818c440f

android/gradle/generate_gradle.py

@@ -745,7 +745,7 @@ def main():
     _ExtractZips(generator.project_dir, zip_tuples)
 
   logging.warning('Project created! (%d subprojects)', len(project_entries))
-  logging.warning('Generated projects work best with Android Studio 2.2')
+  logging.warning('Generated projects work with Android Studio 2.3')
   logging.warning('For more tips: https://chromium.googlesource.com/chromium'
                   '/src.git/+/master/docs/android_studio.md')
 

android/gradle/root.jinja

@@ -8,6 +8,6 @@ buildscript {
         jcenter()
     }
     dependencies {
-        classpath "com.android.tools.build:gradle:2.2.3"
+        classpath "com.android.tools.build:gradle:2.3.0"
     }
 }