docs: Fixed broken urls in the UI testing training main page and revised intro to the 'Testing UI for a Single App' class.

Change-Id: I0e2a49b639101a7607e8e90cf830d9d449ad6328
diff --git a/docs/html/training/testing/ui-testing/espresso-testing.jd b/docs/html/training/testing/ui-testing/espresso-testing.jd
index e5e37f7..85f4ba4 100644
--- a/docs/html/training/testing/ui-testing/espresso-testing.jd
+++ b/docs/html/training/testing/ui-testing/espresso-testing.jd
@@ -60,8 +60,8 @@
-      UI tests that involve user interactions
-      within a single app help to ensure that users do not
+      Testing user interactions
+      within a single app helps to ensure that users do not
       encounter unexpected results or have a poor experience when interacting with your app.
       You should get into the habit of creating user interface (UI) tests if you need to verify
       that the UI of your app is functioning correctly.
diff --git a/docs/html/training/testing/ui-testing/index.jd b/docs/html/training/testing/ui-testing/index.jd
index 605de22..20422f7 100644
--- a/docs/html/training/testing/ui-testing/index.jd
+++ b/docs/html/training/testing/ui-testing/index.jd
@@ -14,7 +14,7 @@
-            <a href="{@docRoot}/tools/testing-support-library/index.html">Testing Support Library</a>
+            <a href="{@docRoot}tools/testing-support-library/index.html">Testing Support Library</a>
@@ -59,10 +59,10 @@
 <p>The lessons in this class teach you how to use the tools and APIs in the
-<a href="{@docRoot}/tools/testing-support-library/index.html">Android Testing Support Library</a>
+<a href="{@docRoot}tools/testing-support-library/index.html">Android Testing Support Library</a>
 to build these types of automated tests. Before you begin building tests using these
 APIs, you must install the Android Testing Support Library, as described in
-<a href="{@docRoot}/tools/testing-support-library/index.html#setup">Downloading the Android
+<a href="{@docRoot}tools/testing-support-library/index.html#setup">Downloading the Android
 Testing Support Library</a>.</p>