Update Eclipse classpath and documentation for running JUnit tests.

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 105 matching lines @@
     <classpathentry kind="src" path="third_party/cacheinvalidation/src/java"/>
     <classpathentry kind="src" path="third_party/custom_tabs_client/src/customtabs/src"/>
     <classpathentry kind="src" path="third_party/custom_tabs_client/src/Application/src/main/java"/>
     <classpathentry kind="src" path="third_party/custom_tabs_client/src/shared/src/main/java"/>
     <classpathentry kind="src" path="third_party/gif_player/src"/>
     <classpathentry kind="src" path="third_party/jmake/src"/>
     <classpathentry kind="src" path="third_party/junit/src/src/main/java"/>
     <classpathentry kind="src" path="third_party/leakcanary/src/leakcanary-android/src/main/java"/>
     <classpathentry kind="src" path="third_party/leakcanary/src/leakcanary-watcher/src/main/java"/>
     <classpathentry kind="src" path="third_party/mockito/src/src/main/java"/>
-    <classpathentry kind="src" path="third_party/robolectric/robolectric/robolectric-annotations/src/main/java"/>
-    <classpathentry kind="src" path="third_party/robolectric/robolectric/robolectric-resources/src/main/java"/>
-    <classpathentry kind="src" path="third_party/robolectric/robolectric/robolectric-shadows/shadows-multidex/src/main/java"/>
     <classpathentry kind="src" path="tools/android/findbugs_plugin/src"/>
     <classpathentry kind="src" path="tools/android/findbugs_plugin/test/java/src"/>
     <classpathentry kind="src" path="tools/android/memconsumer/java/src"/>
     <classpathentry kind="src" path="ui/android/java/src"/>
     <classpathentry kind="src" path="ui/android/javatests/src"/>
     <classpathentry kind="src" path="out/Debug/android_webview_test_apk/gen"/>
     <classpathentry kind="src" path="out/Debug/chrome_public_apk/gen"/>
     <classpathentry kind="src" path="out/Debug/content_shell_apk/gen"/>
     <classpathentry kind="src" path="out/Debug/gen/enums/accessibility_java"/>
     <classpathentry kind="src" path="out/Debug/gen/enums/activity_type_ids_java"/>
@@ skipping 151 matching lines @@
     <classpathentry kind="lib" path="out/Debug/lib.java/sync/android/sync_java.jar"/>
     <classpathentry kind="lib" path="out/Debug/lib.java/sync/test_support_proto_java.jar"/>
     <classpathentry kind="lib" path="out/Debug/lib.java/third_party/android_data_chart/android_data_chart_java.jar"/>
     <classpathentry kind="lib" path="out/Debug/lib.java/third_party/android_media/android_media_java.jar"/>
     <classpathentry kind="lib" path="out/Debug/lib.java/third_party/android_protobuf/protobuf_nano_javalib.jar"/>
     <classpathentry kind="lib" path="out/Debug/lib.java/third_party/android_swipe_refresh/android_swipe_refresh_java.jar"/>
     <classpathentry kind="lib" path="out/Debug/lib.java/third_party/cacheinvalidation/cacheinvalidation_javalib.jar"/>
     <classpathentry kind="lib" path="out/Debug/lib.java/third_party/cacheinvalidation/cacheinvalidation_proto_java.jar"/>
     <classpathentry kind="lib" path="out/Debug/lib.java/third_party/cardboard-java/cardboard-java.jar"/>
     <classpathentry kind="lib" path="out/Debug/lib.java/third_party/gif_player/gif_player_java.jar"/>
+    <classpathentry kind="lib" path="out/Debug/lib.java/third_party/guava/guava-20.0.jar"/>
+    <classpathentry kind="lib" path="out/Debug/lib.java/third_party/robolectric/robolectric_annotations_java.jar" sourcepath="third_party/robolectric/robolectric/robolectric-annotations/src/main/java"/>
     <classpathentry kind="lib" path="out/Debug/lib.java/third_party/robolectric/robolectric_java.jar" sourcepath="third_party/robolectric/robolectric/robolectric/src/main/java"/>
+    <classpathentry kind="lib" path="out/Debug/lib.java/third_party/robolectric/robolectric_resources_java.jar" sourcepath="third_party/robolectric/robolectric/robolectric-resources/src/main/java"/>
     <classpathentry kind="lib" path="out/Debug/lib.java/third_party/robolectric/robolectric_utils_java.jar" sourcepath="third_party/robolectric/robolectric/robolectric-utils/src/main/java"/>
-    <classpathentry kind="lib" path="out/Debug/lib.java/third_party/robolectric/shadows-core-3.0-21.jar" sourcepath="third_party/robolectric/robolectric/robolectric-shadows/shadows-core/src/main/java"/>
+    <classpathentry kind="lib" path="out/Debug/lib.java/third_party/robolectric/shadows-core-3.2.jar" sourcepath="third_party/robolectric/robolectric/robolectric-shadows/shadows-core/src/main/java"/>
     <classpathentry kind="lib" path="out/Debug/lib.java/third_party/robolectric/shadows-multidex-3.0.jar" sourcepath="third_party/robolectric/robolectric/robolectric-shadows/shadows-multidex/src/main/java"/>
     <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"/>
     <classpathentry kind="lib" path="out/Debug/lib.java/ui/base/mojo/mojo_bindings_java.jar"/>
 
     <!-- {% block additional_entries %} -->
     <!-- When this file is processed as a jinja2 template, additional
          <classpathentry> elements will be inserted here. -->
     <!-- {% endblock %} -->
 
 </classpath>