Facebook Android SDK 3.17.2

Summary: Facebook Android SDK 3.17.2 (see https://developers.facebook.com/docs/android/change-log-3.x/)

Test Plan: Built ZIP

Reviewers: gen, jacl, clang, mingfli

Reviewed By: mingfli

Subscribers: dmmiller

Differential Revision: https://phabricator.fb.com/D1512256
Facebook Android SDK 3.18

Summary: Facebook Android SDK 3.18 (see https://developers.facebook.com/docs/android/change-log-3.x/)

Test Plan: Built ZIP

Reviewers: jacl, karthiks, clang

Reviewed By: clang

Subscribers: dmmiller

Differential Revision: https://phabricator.fb.com/D1535048
Merge branch 'master' of https://github.com/facebook/facebook-android-sdk

Conflicts:
	facebook/build.gradle