Introduce ThreadedInputConnection behind a switch

tools/android/eclipse/.classpath

 <?xml version="1.0" encoding="UTF-8"?>
 <!-- {% block header_message %}
 
 Eclipse classpath. See instructions at
 https://www.chromium.org/developers/android-eclipse-dev for setting up Eclipse
 for Chrome Android development.
 
 Obsolete entries can be found using:
 
   for f in $(grep -oP '(?<= path=")[^"]*' tools/android/eclipse/.classpath); do
@@ skipping 32 matching lines @@
     <classpathentry kind="src" path="components/navigation_interception/android/java/src"/>
     <classpathentry kind="src" path="components/policy/android/java/src"/>
     <classpathentry kind="src" path="components/precache/android/java/src"/>
     <classpathentry kind="src" path="components/precache/android/javatests/src"/>
     <classpathentry kind="src" path="components/safe_json/android/java/src"/>
     <classpathentry kind="src" path="components/service_tab_launcher/android/java/src"/>
     <classpathentry kind="src" path="components/variations/android/java/src"/>
     <classpathentry kind="src" path="components/web_contents_delegate_android/android/java/src"/>
     <classpathentry kind="src" path="content/public/android/java/src"/>
     <classpathentry kind="src" path="content/public/android/javatests/src"/>
+    <classpathentry kind="src" path="content/public/android/junit/src"/>
     <classpathentry kind="src" path="content/public/test/android/javatests/src"/>
     <classpathentry kind="src" path="content/shell/android/browsertests/src"/>
     <classpathentry kind="src" path="content/shell/android/browsertests_apk/src"/>
     <classpathentry kind="src" path="content/shell/android/java/src"/>
     <classpathentry kind="src" path="content/shell/android/javatests/src"/>
     <classpathentry kind="src" path="content/shell/android/linker_test_apk/src"/>
     <classpathentry kind="src" path="content/shell/android/shell_apk/src"/>
     <classpathentry kind="src" path="device/battery/android/java/src"/>
     <classpathentry kind="src" path="media/base/android/java/src"/>
     <classpathentry kind="src" path="mojo/android/system/src"/>
@@ skipping 168 matching lines @@
     <classpathentry kind="lib" path="out/Debug/lib.java/third_party/WebKit/public/blink_headers_java.jar"/>
     <classpathentry kind="lib" path="out/Debug/lib.java/ui/accessibility/ui_accessibility_java.jar"/>
     <classpathentry kind="lib" path="out/Debug/lib.java/ui/android/ui_java.jar"/>
 
     <!-- {% block additional_entries %} -->
     <!-- When this file is processed as a jinja2 template, additional
          <classpathentry> elements will be inserted here. -->
     <!-- {% endblock %} -->
 
 </classpath>