[RN] Fix running timers in the background

Turns out React Native's timers (setTimeout / setInterval) don't run while the
app is in the background: https://github.com/facebook/react-native/issues/167

This patch replaces the global timer functions with those from the
react-native-background-timer package, which work in the background.

These timers won't magically make an application work in the background, but
they will run if an application already happens to run in the background. That's
our case while in a conference, so these timers will run, allowing XMPP pings to
be sent and the conference to stay up as long as the user desires.

android/app/build.gradle

 }
 
 dependencies {
+    compile project(':react-native-background-timer')
     compile project(':react-native-immersive')
     compile project(':react-native-keep-awake')
     compile project(':react-native-vector-icons')

android/app/src/main/java/org/jitsi/meet/MainApplication.java

                 new com.corbt.keepawake.KCKeepAwakePackage(),
                 new com.facebook.react.shell.MainReactPackage(),
                 new com.oblador.vectoricons.VectorIconsPackage(),
+                new com.ocetnik.timer.BackgroundTimerPackage(),
                 new com.oney.WebRTCModule.WebRTCModulePackage(),
                 new com.rnimmersive.RNImmersivePackage(),
                 new org.jitsi.meet.audiomode.AudioModePackage()

android/settings.gradle

 rootProject.name = 'jitsi-meet-react'
 
 include ':app'
+include ':react-native-background-timer'
+project(':react-native-background-timer').projectDir = new File(rootProject.projectDir, '../node_modules/react-native-background-timer/android')
 include ':react-native-immersive'
 project(':react-native-immersive').projectDir = new File(rootProject.projectDir, '../node_modules/react-native-immersive/android')
 include ':react-native-keep-awake'

ios/jitsi-meet-react.xcodeproj/project.pbxproj

 	};
 	objectVersion = 46;
 	objects = {
-
 /* Begin PBXBuildFile section */
 		002AF788986B412780935607 /* FontAwesome.ttf in Resources */ = {isa = PBXBuildFile; fileRef = B96AF9B6FBC0453798399985 /* FontAwesome.ttf */; };
 		00C302E51ABCBA2D00DB3ED1 /* libRCTActionSheet.a in Frameworks */ = {isa = PBXBuildFile; fileRef = 00C302AC1ABCB8CE00DB3ED1 /* libRCTActionSheet.a */; };
 		BF9643921C34FBF100B0BBDF /* libsqlite3.tbd in Frameworks */ = {isa = PBXBuildFile; fileRef = BF9643911C34FBF100B0BBDF /* libsqlite3.tbd */; };
 		BF9643941C34FBF900B0BBDF /* libstdc++.tbd in Frameworks */ = {isa = PBXBuildFile; fileRef = BF9643931C34FBF900B0BBDF /* libstdc++.tbd */; };
 		BFC745141CB829B300673F38 /* libRCTWebRTC.a in Frameworks */ = {isa = PBXBuildFile; fileRef = BFC745131CB829A700673F38 /* libRCTWebRTC.a */; };
+		7FAD39BE09A84D6AB0ABACA8 /* libRNBackgroundTimer.a in Frameworks */ = {isa = PBXBuildFile; fileRef = 27A0018BBB2C4FD5A4F9CE71 /* libRNBackgroundTimer.a */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXContainerItemProxy section */
 		BF9643911C34FBF100B0BBDF /* libsqlite3.tbd */ = {isa = PBXFileReference; lastKnownFileType = "sourcecode.text-based-dylib-definition"; name = libsqlite3.tbd; path = usr/lib/libsqlite3.tbd; sourceTree = SDKROOT; };
 		BF9643931C34FBF900B0BBDF /* libstdc++.tbd */ = {isa = PBXFileReference; lastKnownFileType = "sourcecode.text-based-dylib-definition"; name = "libstdc++.tbd"; path = "usr/lib/libstdc++.tbd"; sourceTree = SDKROOT; };
 		BFC7450D1CB829A700673F38 /* RCTWebRTC.xcodeproj */ = {isa = PBXFileReference; lastKnownFileType = "wrapper.pb-project"; name = RCTWebRTC.xcodeproj; path = "../node_modules/react-native-webrtc/ios/RCTWebRTC.xcodeproj"; sourceTree = "<group>"; };
+		0965153BB98645B4A8B6AA10 /* RNBackgroundTimer.xcodeproj */ = {isa = PBXFileReference; name = "RNBackgroundTimer.xcodeproj"; path = "../node_modules/react-native-background-timer/ios/RNBackgroundTimer.xcodeproj"; sourceTree = "<group>"; fileEncoding = undefined; lastKnownFileType = wrapper.pb-project; explicitFileType = undefined; includeInIndex = 0; };
+		27A0018BBB2C4FD5A4F9CE71 /* libRNBackgroundTimer.a */ = {isa = PBXFileReference; name = "libRNBackgroundTimer.a"; path = "libRNBackgroundTimer.a"; sourceTree = "<group>"; fileEncoding = undefined; lastKnownFileType = archive.ar; explicitFileType = undefined; includeInIndex = 0; };
 /* End PBXFileReference section */
 
 /* Begin PBXFrameworksBuildPhase section */
 				139FDEF61B0652A700C62182 /* libRCTWebSocket.a in Frameworks */,
 				3847F11906B4479A9162628F /* libRNVectorIcons.a in Frameworks */,
 				901FE90FA5744B5B94DCDC41 /* libKCKeepAwake.a in Frameworks */,
+				7FAD39BE09A84D6AB0ABACA8 /* libRNBackgroundTimer.a in Frameworks */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
 				139FDEE61B06529A00C62182 /* RCTWebSocket.xcodeproj */,
 				146833FF1AC3E56700842450 /* React.xcodeproj */,
 				22418656B14845609F953A42 /* RNVectorIcons.xcodeproj */,
+				0965153BB98645B4A8B6AA10 /* RNBackgroundTimer.xcodeproj */,
 			);
 			name = Libraries;
 			sourceTree = "<group>";
 		83CBB9F71A601CBA00E9B192 /* Project object */ = {
 			isa = PBXProject;
 			attributes = {
-				LastUpgradeCheck = 0820;
+				LastUpgradeCheck = 820;
 				ORGANIZATIONNAME = Facebook;
 				TargetAttributes = {
 					13B07F861A680F5B00A75B9A = {
 					"$(SRCROOT)/../node_modules/react-native/Libraries/LinkingIOS/**",
 					"$(SRCROOT)/../node_modules/react-native-keep-awake/ios",
 					"$(SRCROOT)/../node_modules/react-native-vector-icons/RNVectorIconsManager",
+					"$(SRCROOT)/../node_modules/react-native-background-timer/ios",
 				);
 				INFOPLIST_FILE = app/Info.plist;
 				IPHONEOS_DEPLOYMENT_TARGET = 9.0;
 				LIBRARY_SEARCH_PATHS = (
 					"$(inherited)",
 					"$(SRCROOT)/../node_modules/react-native-webrtc/**",
+					"\"$(SRCROOT)/jitsi-meet-react\"",
 				);
 				OTHER_LDFLAGS = (
 					"$(inherited)",
 					"$(SRCROOT)/../node_modules/react-native/Libraries/LinkingIOS/**",
 					"$(SRCROOT)/../node_modules/react-native-keep-awake/ios",
 					"$(SRCROOT)/../node_modules/react-native-vector-icons/RNVectorIconsManager",
+					"$(SRCROOT)/../node_modules/react-native-background-timer/ios",
 				);
 				INFOPLIST_FILE = app/Info.plist;
 				IPHONEOS_DEPLOYMENT_TARGET = 9.0;
 				LIBRARY_SEARCH_PATHS = (
 					"$(inherited)",
 					"$(SRCROOT)/../node_modules/react-native-webrtc/**",
+					"\"$(SRCROOT)/jitsi-meet-react\"",
 				);
 				OTHER_LDFLAGS = (
 					"$(inherited)",
 					"$(SRCROOT)/../node_modules/react-native/React/**",
 					"$(SRCROOT)/../node_modules/react-native-keep-awake/ios",
 					"$(SRCROOT)/../node_modules/react-native-vector-icons/RNVectorIconsManager",
+					"$(SRCROOT)/../node_modules/react-native-background-timer/ios",
 				);
 				IPHONEOS_DEPLOYMENT_TARGET = 8.0;
 				MTL_ENABLE_DEBUG_INFO = YES;
 					"$(SRCROOT)/../node_modules/react-native/React/**",
 					"$(SRCROOT)/../node_modules/react-native-keep-awake/ios",
 					"$(SRCROOT)/../node_modules/react-native-vector-icons/RNVectorIconsManager",
+					"$(SRCROOT)/../node_modules/react-native-background-timer/ios",
 				);
 				IPHONEOS_DEPLOYMENT_TARGET = 8.0;
 				MTL_ENABLE_DEBUG_INFO = NO;

package.json

     "react": "15.4.2",
     "react-dom": "15.4.2",
     "react-native": "0.41.2",
+    "react-native-background-timer": "^1.0.0",
     "react-native-immersive": "0.0.4",
     "react-native-keep-awake": "^2.0.2",
     "react-native-prompt": "^1.0.0",

react/features/base/lib-jitsi-meet/native/polyfills-browser.js

+import BackgroundTimer from 'react-native-background-timer';
+
 /**
  * Gets the first common prototype of two specified Objects (treating the
  * objects themselves as prototypes as well).
         }
     }
 
+    // Timers
+    //
+    // React Native's timers won't run while the app is in the background,
+    // this is a known limitation. Replace them with a background-friendly
+    // alternative.
+    //
+    // Required by:
+    // - lib-jitsi-meet
+    // - Strophe
+    global.setTimeout = window.setTimeout = BackgroundTimer.setTimeout;
+    global.clearTimeout = window.clearTimeout = BackgroundTimer.clearTimeout;
+    global.setInterval = window.setInterval = BackgroundTimer.setInterval;
+    global.clearInterval = window.clearInterval = BackgroundTimer.clearInterval;
+
 })(global || window || this); // eslint-disable-line no-invalid-this