Android: Split up build.gradle.jinja

build/android/gradle/root.jinja

Index: build/android/gradle/root.jinja
diff --git a/build/android/gradle/root.jinja b/build/android/gradle/root.jinja
new file mode 100644
index 0000000000000000000000000000000000000000..52f0edae3a0e308188b56cdc13be574adb90b787
--- /dev/null
+++ b/build/android/gradle/root.jinja
@@ -0,0 +1,13 @@
+{# Copyright 2016 The Chromium Authors. All rights reserved. #}
+{# Use of this source code is governed by a BSD-style license that can be #}
+{# found in the LICENSE file. #}
+// Generated by //build/android/generate_gradle.py
+
+buildscript {
+    repositories {
+        jcenter()
+    }
+    dependencies {
+        classpath "com.android.tools.build:gradle:2.2.3"
+    }
+}