android: config changes to build with ant

Change-Id: I6c7030bcc6a2f3bb882af706a8cab2a126faef8c

clients/android/build.xml

@@ -34,34 +34,39 @@
          should be checked in in Version Control Systems. -->
     <property file="default.properties" />
 
-    <!-- Custom Android task to deal with the project target, and import the proper rules.
-         This requires ant 1.6.0 or above. -->
-    <path id="android.antlibs">
-        <pathelement path="${sdk.dir}/tools/lib/anttasks.jar" />
-        <pathelement path="${sdk.dir}/tools/lib/sdklib.jar" />
-        <pathelement path="${sdk.dir}/tools/lib/androidprefs.jar" />
-        <pathelement path="${sdk.dir}/tools/lib/apkbuilder.jar" />
-        <pathelement path="${sdk.dir}/tools/lib/jarutils.jar" />
-    </path>
-
-    <taskdef name="setup"
-        classname="com.android.ant.SetupTask"
-        classpathref="android.antlibs" />
-
-    <!-- Execute the Android Setup task that will setup some properties specific to the target,
-         and import the build rules files.
-
-         The rules file is imported from
-            <SDK>/platforms/<target_platform>/templates/android_rules.xml
-
-         To customize some build steps for your project:
-         - copy the content of the main node <project> from android_rules.xml
-         - paste it in this build.xml below the <setup /> task.
-         - disable the import by changing the setup task below to <setup import="false" />
-
-         This will ensure that the properties are setup correctly but that your customized
-         build steps are used.
+    <!--
+        Import per project custom build rules if present at the root of the project.
+        This is the place to put custom intermediary targets such as:
+            -pre-build
+            -pre-compile
+            -post-compile (This is typically used for code obfuscation.
+                           Compiled code location: ${out.classes.absolute.dir}
+                           If this is not done in place, override ${out.dex.input.absolute.dir})
+            -post-package
+            -post-build
+            -pre-clean
     -->
-    <setup />
+    <import file="custom_rules.xml" optional="true" />
+
+    <!-- Import the actual build file.
+
+         To customize existing targets, there are two options:
+         - Customize only one target:
+             - copy/paste the target into this file, *before* the
+               <import> task.
+             - customize it to your needs.
+         - Customize the whole content of build.xml
+             - copy/paste the content of the rules files (minus the top node)
+               into this file, replacing the <import> task.
+             - customize to your needs.
+
+         ***********************
+         ****** IMPORTANT ******
+         ***********************
+         In all cases you must update the value of version-tag below to read 'custom' instead of an integer,
+         in order to avoid having your file be overridden by tools such as "android update project"
+    -->
+    <!-- version-tag: 1 -->
+    <import file="${sdk.dir}/tools/ant/build.xml" />
 
 </project>

clients/android/default.properties

@@ -8,5 +8,5 @@
 # project structure.
 
 # Project target.
-target=android-10
+target=android-17
 

clients/android/project.properties

@@ -11,4 +11,4 @@
 #proguard.config=${sdk.dir}/tools/proguard/proguard-android.txt:proguard-project.txt
 
 # Project target.
-target=android-10
+target=android-17