Merge pull request #1081 from react-native-community/revert-1080-revert-999-master

Reapply "Using SDK Version variables from root project""

android-exoplayer/build.gradle

@@ -1,17 +1,28 @@
 apply plugin: 'com.android.library'
 
+def _ext = rootProject.ext
+
+def _reactNativeVersion = _ext.has('reactNative') ? _ext.reactNative : '+'
+def _compileSdkVersion = _ext.has('compileSdkVersion') ? _ext.compileSdkVersion : 27
+def _buildToolsVersion = _ext.has('buildToolsVersion') ? _ext.buildToolsVersion : '27.0.3'
+def _minSdkVersion = _ext.has('minSdkVersion') ? _ext.minSdkVersion : 16
+def _targetSdkVersion = _ext.has('targetSdkVersion') ? _ext.targetSdkVersion : 27
+
 android {
-    compileSdkVersion 23
-    buildToolsVersion "25.0.2"
+    compileSdkVersion _compileSdkVersion
+    buildToolsVersion _buildToolsVersion
 
     defaultConfig {
-        minSdkVersion 16
-        targetSdkVersion 23
+        minSdkVersion _minSdkVersion
+        targetSdkVersion _targetSdkVersion
+        versionCode 1
+        versionName "1.0"
     }
 }
 
 dependencies {
-    provided 'com.facebook.react:react-native:+'
+    //noinspection GradleDynamicVersion
+    provided "com.facebook.react:react-native:${_reactNativeVersion}"
     compile 'com.google.android.exoplayer:exoplayer:2.7.3'
     compile('com.google.android.exoplayer:extension-okhttp:2.7.3') {
         exclude group: 'com.squareup.okhttp3', module: 'okhttp'