Make libjingle Android example build without sourcing envsetup.sh
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: a556c8bde68cedbc0208a1ffc78b06e9cd07f676@5908 4adac7df-926f-26a2-2b94-8c16560cd09d

AOSPU/external_chromium_org_third_party_libjingle_source_talk,bpsinc-native/src_third_party_libjingle_source_talk,android-ia/platform_external_chromium_org_third_party_libjingle_source_talk,bpsinc-native/src_third_party_libjingle_source_talk,android-ia/platform_external_chromium_org_third_party_libjingle_source_talk,dcpang/fatline-libjingle,dcpang/fatline-libjingle,sippet/talk,geekboxzone/lollipop_external_chromium_org_third_party_libjingle_source_talk,android-ia/platform_external_chromium_org_third_party_libjingle_source_talk,AOSPU/external_chromium_org_third_party_libjingle_source_talk,geekboxzone/lollipop_external_chromium_org_third_party_libjingle_source_talk,android-ia/platform_external_chromium_org_third_party_libjingle_source_talk,geekboxzone/lollipop_external_chromium_org_third_party_libjingle_source_talk,Omegaphora/external_chromium_org_third_party_libjingle_source_talk,Omegaphora/external_chromium_org_third_party_libjingle_source_talk,Omegaphora/external_chromium_org_third_party_libjingle_source_talk,Omegaphora/external_chromium_org_third_party_libjingle_source_talk,bpsinc-native/src_third_party_libjingle_source_talk,geekboxzone/lollipop_external_chromium_org_third_party_libjingle_source_talk,sippet/talk,AOSPU/external_chromium_org_third_party_libjingle_source_talk,dcpang/fatline-libjingle,sippet/talk,bpsinc-native/src_third_party_libjingle_source_talk,xin3liang/platform_external_chromium_org_third_party_libjingle_source_talk,geekboxzone/lollipop_external_chromium_org_third_party_libjingle_source_talk,bpsinc-native/src_third_party_libjingle_source_talk,sippet/talk,dcpang/fatline-libjingle,xin3liang/platform_external_chromium_org_third_party_libjingle_source_talk,Omegaphora/external_chromium_org_third_party_libjingle_source_talk,sippet/talk,dcpang/fatline-libjingle,xin3liang/platform_external_chromium_org_third_party_libjingle_source_talk,xin3liang/platform_external_chromium_org_third_party_libjingle_source_talk,android-ia/platform_external_chromium_org_third_party_libjingle_source_talk,android-ia/platform_external_chromium_org_third_party_libjingle_source_talk,xin3liang/platform_external_chromium_org_third_party_libjingle_source_talk,AOSPU/external_chromium_org_third_party_libjingle_source_talk,bpsinc-native/src_third_party_libjingle_source_talk,AOSPU/external_chromium_org_third_party_libjingle_source_talk,Omegaphora/external_chromium_org_third_party_libjingle_source_talk