[android] Updated Facebook auidience SDK to 4.20.0

[android] Enabled multidex support

android/build.gradle

@@ -48,7 +48,7 @@ dependencies {
   compile('com.crashlytics.sdk.android:crashlytics-ndk:1.1.2@aar') { transitive = true }
   // 3-party
   compile 'com.facebook.android:facebook-android-sdk:4.8.0'
-  compile('com.facebook.android:audience-network-sdk:4.8.0') {
+  compile('com.facebook.android:audience-network-sdk:4.20.0') {
     exclude group: 'com.google.android.gms'
   }
   compile 'com.google.code.gson:gson:2.6.1'
@@ -65,6 +65,7 @@ dependencies {
   compile 'com.github.bumptech.glide:glide:3.7.0'
   // Java concurrency annotations
   compile 'net.jcip:jcip-annotations:1.0'
+  compile 'com.android.support:multidex:1.0.1'
 }
 
 def getDate() {
@@ -110,6 +111,7 @@ android {
     manifestPlaceholders += ['PW_APPID': pwProps['pwAppId']]
     buildConfigField 'String', 'PW_APPID', /"${pwProps['pwAppId']}"/
     manifestPlaceholders += ['PW_PROJECT_ID': pwProps['pwProjectId']]
+    multiDexEnabled true
   }
 
   sourceSets.main {

android/src/com/mapswithme/maps/MwmApplication.java

@@ -1,6 +1,7 @@
 package com.mapswithme.maps;
 
 import android.app.Application;
+import android.content.Context;
 import android.content.SharedPreferences;
 import android.content.pm.PackageManager.NameNotFoundException;
 import android.os.Environment;
@@ -9,6 +10,7 @@ import android.os.Message;
 import android.preference.PreferenceManager;
 import android.support.annotation.NonNull;
 import android.support.annotation.UiThread;
+import android.support.multidex.MultiDex;
 import android.text.TextUtils;
 import android.util.Log;
 
@@ -128,6 +130,13 @@ public class MwmApplication extends Application
     return !BuildConfig.FABRIC_API_KEY.startsWith("0000");
   }
 
+  @Override
+  protected void attachBaseContext(Context base)
+  {
+    super.attachBaseContext(base);
+    MultiDex.install(this);
+  }
+
   @SuppressWarnings("ResultOfMethodCallIgnored")
   @Override
   public void onCreate()

android/src/com/mapswithme/maps/widget/placepage/BannerController.java

@@ -254,7 +254,7 @@ final class BannerController implements AdListener
     updateVisibility();
 
     BannerData newData = new BannerData(mNativeAd);
-    LOGGER.d(TAG, "A new banner was loaded");
+    LOGGER.d(TAG, "A new banner was loaded with placement id '" + ad.getPlacementId() + "'");
 
     // In general, if there is a cached banner, we have to show it instead of a just-downloaded banner.
     // Thus, we try to eliminate a number of situations when user sees a blank banner view until