Make libjingle Android example build without sourcing envsetup.sh

See https://webrtc-codereview.appspot.com/11799004
for full details (separate to avoid webrtc+talk changes in same CL).

BUG=chromium:346198
TEST=Local builds using:
. build/android/envsetup.sh
unset ANDROID_SDK_ROOT
webrtc/build/gyp_webrtc
ninja -C out/Debug
ninja -C out/Release
+ trybots passing: git try --bot=android,android_rel,android_clang

R=fischman@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/11809004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@5908 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/talk/libjingle_examples.gyp b/talk/libjingle_examples.gyp
index cfae741..0648ec0 100755
--- a/talk/libjingle_examples.gyp
+++ b/talk/libjingle_examples.gyp
@@ -318,7 +318,8 @@
                 'cp <(PRODUCT_DIR)/libjingle_peerconnection.jar examples/android/libs/ &&'
                 '<(android_strip) -o examples/android/libs/<(android_app_abi)/libjingle_peerconnection_so.so  <(PRODUCT_DIR)/libjingle_peerconnection_so.so &&'
                 'cd examples/android && '
-                '{ ant debug > <(ant_log) 2>&1 || '
+                '{ ANDROID_SDK_ROOT=<(android_sdk_root) '
+                'ant debug > <(ant_log) 2>&1 || '
                 '  { cat <(ant_log) ; exit 1; } } && '
                 'cd - > /dev/null && '
                 'cp examples/android/bin/AppRTCDemo-debug.apk <(_outputs)'