Switch incorrectly configured native multidex to legacy

Native multidex can only be used for binaries with minSdkVersion of 21 or higher, but minSdkVersion was specified to 16.

PiperOrigin-RevId: 470003836
(cherry picked from commit 142d1c06)

extensions/cronet/src/androidTest/AndroidManifest.xml

@@ -22,7 +22,9 @@
   <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
   <uses-sdk/>
 
+  <!-- TODO(b/243799715): Use android:name="androidx.multidex.MultiDexApplication" instead. -->
   <application
+    android:name="android.support.multidex.MultiDexApplication"
     android:allowBackup="false"
     android:usesCleartextTraffic="true"
     tools:ignore="MissingApplicationIcon,HardcodedDebugMode"/>

extensions/flac/src/androidTest/AndroidManifest.xml

@@ -21,7 +21,9 @@
   <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
   <uses-sdk/>
 
+  <!-- TODO(b/243799715): Use android:name="androidx.multidex.MultiDexApplication" instead. -->
   <application
+      android:name="android.support.multidex.MultiDexApplication"
       android:allowBackup="false"
       tools:ignore="MissingApplicationIcon,HardcodedDebugMode"/>
 

extensions/ima/src/androidTest/AndroidManifest.xml

@@ -23,7 +23,9 @@
   <uses-permission android:name="android.permission.WAKE_LOCK"/>
   <uses-sdk/>
 
+  <!-- TODO(b/243799715): Use android:name="androidx.multidex.MultiDexApplication" instead. -->
   <application
+      android:name="android.support.multidex.MultiDexApplication"
       android:allowBackup="false"
       tools:ignore="MissingApplicationIcon,HardcodedDebugMode">
     <activity android:name="com.google.android.exoplayer2.testutil.HostActivity"

extensions/media2/src/androidTest/AndroidManifest.xml

@@ -22,6 +22,12 @@
   <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
   <uses-sdk/>
 
+  <!-- TODO(b/243799715): Use android:name="androidx.multidex.MultiDexApplication" instead. -->
+  <application
+    android:name="android.support.multidex.MultiDexApplication"
+    android:allowBackup="false"
+    tools:ignore="MissingApplicationIcon,HardcodedDebugMode"/>
+
   <instrumentation
       android:targetPackage="com.google.android.exoplayer2.ext.media2.test"
       android:name="androidx.test.runner.AndroidJUnitRunner"/>

extensions/opus/src/androidTest/AndroidManifest.xml

@@ -21,7 +21,9 @@
   <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
   <uses-sdk/>
 
+  <!-- TODO(b/243799715): Use android:name="androidx.multidex.MultiDexApplication" instead. -->
   <application
+      android:name="android.support.multidex.MultiDexApplication"
       android:allowBackup="false"
       tools:ignore="MissingApplicationIcon,HardcodedDebugMode"/>
 

extensions/vp9/src/androidTest/AndroidManifest.xml

@@ -21,7 +21,9 @@
   <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
   <uses-sdk/>
 
+  <!-- TODO(b/243799715): Use android:name="androidx.multidex.MultiDexApplication" instead. -->
   <application
+      android:name="android.support.multidex.MultiDexApplication"
       android:allowBackup="false"
       tools:ignore="MissingApplicationIcon,HardcodedDebugMode"/>
 

library/core/src/androidTest/AndroidManifest.xml

@@ -22,7 +22,9 @@
   <uses-permission android:name="android.permission.INTERNET"/>
   <uses-sdk/>
 
+  <!-- TODO(b/243799715): Use android:name="androidx.multidex.MultiDexApplication" instead. -->
   <application
+      android:name="android.support.multidex.MultiDexApplication"
       android:allowBackup="false"
       tools:ignore="MissingApplicationIcon,HardcodedDebugMode"
       android:usesCleartextTraffic="true"/>

library/datasource/src/androidTest/AndroidManifest.xml

@@ -21,7 +21,9 @@
   <uses-permission android:name="android.permission.INTERNET"/>
   <uses-sdk/>
 
+  <!-- TODO(b/243799715): Use android:name="androidx.multidex.MultiDexApplication" instead. -->
   <application
+      android:name="android.support.multidex.MultiDexApplication"
       android:allowBackup="false"
       android:usesCleartextTraffic="true"
       tools:ignore="MissingApplicationIcon,HardcodedDebugMode">

playbacktests/src/androidTest/AndroidManifest.xml

@@ -23,7 +23,9 @@
   <uses-permission android:name="android.permission.WAKE_LOCK"/>
   <uses-sdk/>
 
+  <!-- TODO(b/243799715): Use android:name="androidx.multidex.MultiDexApplication" instead. -->
   <application
+      android:name="android.support.multidex.MultiDexApplication"
       android:allowBackup="false"
       tools:ignore="MissingApplicationIcon,HardcodedDebugMode">
     <activity android:name="com.google.android.exoplayer2.testutil.HostActivity"