Clean up SendDialog.java

mytracks_send_to_google.xml
- remove unused ids.
- rename id variables.
- set textSize to 18dip to fit "Google Fusion Tables".
- set margin in ScrollView because its height is 0dip
  and settings margins in its children have no effect.

SendDialog.java
- use ApiFeature.applyPreferenceChanges to commit preference changes.
- set myMapsGroup View to GONE when 'Google My Maps' is not checked.
- use Context.MODE_PRIVATE.
- onStop, call super.onStop first.

MyTracksApiSample/res/layout/main.xml

@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_height="match_parent"
+    android:layout_width="match_parent"
+    android:orientation="vertical"
+    >
+  <Button android:id="@+id/start_recording_button"
+    android:layout_height="wrap_content"
+    android:layout_width="wrap_content"
+    android:text="@string/start_recording"
+    />
+  <Button android:id="@+id/stop_recording_button"
+    android:layout_height="wrap_content"
+    android:layout_width="wrap_content"
+    android:text="@string/stop_recording"
+    />
+  <Button android:id="@+id/add_waypoints_button"
+    android:layout_height="wrap_content"
+    android:layout_width="wrap_content"
+    android:text="@string/add_waypoints"
+    />
+  <TextView android:id="@+id/output"  
+    android:layout_height="wrap_content" 
+    android:layout_width="match_parent"
+    />
+</LinearLayout>

MyTracksApiSample/res/values/strings.xml

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <string name="add_waypoints">Add a waypoint to all the tracks</string>
+    <string name="app_name">MyTracksApiSample</string>
+    <string name="start_recording">Start recording</string>
+    <string name="stop_recording">Stop recording</string>
+</resources>