Revert "Target SDK level 27 in AppRTCMobile."

This reverts commit af4f1b41277ebdf0d7386cbd2903abc709cbc183.

Reason for revert: Causes timeouts with loopback tests. Reverting and
investigating.

Original change's description:
> Target SDK level 27 in AppRTCMobile.
> 
> Implements the dynamic permission model required by the newer SDK and
> changes the theme.
> 
> Bug: webrtc:8803
> Change-Id: I3ea23a25b27f196fcffd018c7cdd2ff6255b62d9
> Reviewed-on: https://webrtc-review.googlesource.com/44400
> Commit-Queue: Sami Kalliomäki <sakal@webrtc.org>
> Reviewed-by: Anders Carlsson <andersc@webrtc.org>
> Cr-Commit-Position: refs/heads/master@{#21788}

TBR=sakal@webrtc.org,andersc@webrtc.org

Change-Id: I4074c48fc7c7466765793244a5a7f60029bc7937
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: webrtc:8803
Reviewed-on: https://webrtc-review.googlesource.com/45980
Reviewed-by: Sami Kalliomäki <sakal@webrtc.org>
Commit-Queue: Sami Kalliomäki <sakal@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#21797}

examples/androidapp/AndroidManifest.xml

@@ -8,7 +8,7 @@
     <uses-feature android:name="android.hardware.camera" />
     <uses-feature android:name="android.hardware.camera.autofocus" />
     <uses-feature android:glEsVersion="0x00020000" android:required="true" />
-    <uses-sdk android:minSdkVersion="16" android:targetSdkVersion="27" />
+    <uses-sdk android:minSdkVersion="16" android:targetSdkVersion="21" />
 
     <uses-permission android:name="android.permission.CAMERA" />
     <uses-permission android:name="android.permission.CHANGE_NETWORK_STATE" />
@@ -30,8 +30,7 @@
 
         <activity android:name="ConnectActivity"
                   android:label="@string/app_name"
-                  android:windowSoftInputMode="adjustPan"
+                  android:windowSoftInputMode="adjustPan">
-                  android:theme="@style/AppTheme">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN"/>
                 <category android:name="android.intent.category.LAUNCHER"/>
@@ -47,8 +46,7 @@
         </activity>
 
         <activity android:name="SettingsActivity"
-                  android:label="@string/settings_name"
+                  android:label="@string/settings_name">
-                  android:theme="@style/AppTheme">
         </activity>
 
         <activity android:name="CallActivity"

examples/androidapp/res/values-v17/styles.xml

@@ -1,7 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
 <resources>
-  <style name="AppTheme" parent="android:Theme.Holo" />
-
   <style name="CallActivityTheme" parent="android:Theme.Black">
     <item name="android:windowActionBar">false</item>
     <item name="android:windowFullscreen">true</item>

examples/androidapp/res/values-v21/styles.xml

@@ -1,4 +1,8 @@
 <?xml version="1.0" encoding="utf-8"?>
 <resources>
-  <style name="AppTheme" parent="android:Theme.Material" />
+  <style name="AppRTCMobileActivityTheme" parent="android:Theme.Material">
+    <item name="android:windowActionBar">false</item>
+    <item name="android:windowFullscreen">true</item>
+    <item name="android:windowNoTitle">true</item>
+  </style>
 </resources>

examples/androidapp/res/values/strings.xml

@@ -27,9 +27,6 @@
     <string name="connect_description">Connect to the room</string>
     <string name="add_favorite_description">Add favorite</string>
     <string name="format_description">%1$dx%2$d @ %3$d fps</string>
-    <string name="missing_permissions_try_again">The application is missing permissions. It might not work correctly. Do you want to try again?</string>
-    <string name="yes">Yes</string>
-    <string name="no">No</string>
 
     <!-- Settings strings. -->
     <string name="pref_room_key">room_preference</string>

examples/androidapp/src/org/appspot/apprtc/ConnectActivity.java

@@ -10,17 +10,12 @@
 
 package org.appspot.apprtc;
 
-import android.Manifest;
-import android.annotation.TargetApi;
 import android.app.Activity;
 import android.app.AlertDialog;
 import android.content.DialogInterface;
 import android.content.Intent;
 import android.content.SharedPreferences;
-import android.content.pm.PackageInfo;
-import android.content.pm.PackageManager;
 import android.net.Uri;
-import android.os.Build;
 import android.os.Bundle;
 import android.preference.PreferenceManager;
 import android.util.Log;
@@ -49,7 +44,6 @@ import org.json.JSONException;
 public class ConnectActivity extends Activity {
   private static final String TAG = "ConnectActivity";
   private static final int CONNECTION_REQUEST = 1;
-  private static final int PERMISSION_REQUEST = 2;
   private static final int REMOVE_FAVORITE_INDEX = 0;
   private static boolean commandLineRun = false;
 
@@ -110,7 +104,16 @@ public class ConnectActivity extends Activity {
     addFavoriteButton = findViewById(R.id.add_favorite_button);
     addFavoriteButton.setOnClickListener(addFavoriteListener);
 
-    requestPermissions();
+    // If an implicit VIEW intent is launching the app, go directly to that URL.
+    final Intent intent = getIntent();
+    if ("android.intent.action.VIEW".equals(intent.getAction()) && !commandLineRun) {
+      boolean loopback = intent.getBooleanExtra(CallActivity.EXTRA_LOOPBACK, false);
+      int runTimeMs = intent.getIntExtra(CallActivity.EXTRA_RUNTIME, 0);
+      boolean useValuesFromIntent =
+          intent.getBooleanExtra(CallActivity.EXTRA_USE_VALUES_FROM_INTENT, false);
+      String room = sharedPref.getString(keyprefRoom, "");
+      connectToRoom(room, true, loopback, useValuesFromIntent, runTimeMs);
+    }
   }
 
   @Override
@@ -207,101 +210,6 @@ public class ConnectActivity extends Activity {
     }
   }
 
-  @Override
-  public void onRequestPermissionsResult(
-      int requestCode, String[] permissions, int[] grantResults) {
-    if (requestCode == PERMISSION_REQUEST) {
-      String[] missingPermissions = getMissingPermissions();
-      if (missingPermissions.length != 0) {
-        // User didn't grant all the permissions. Warn that the application might not work
-        // correctly.
-        new AlertDialog.Builder(this)
-            .setMessage(R.string.missing_permissions_try_again)
-            .setPositiveButton(R.string.yes,
-                (dialog, id) -> {
-                  // User wants to try giving the permissions again.
-                  dialog.cancel();
-                  requestPermissions();
-                })
-            .setNegativeButton(R.string.no,
-                (dialog, id) -> {
-                  // User doesn't want to give the permissions.
-                  dialog.cancel();
-                  onPermissionsGranted();
-                })
-            .show();
-      } else {
-        // All permissions granted.
-        onPermissionsGranted();
-      }
-    }
-  }
-
-  private void onPermissionsGranted() {
-    // If an implicit VIEW intent is launching the app, go directly to that URL.
-    final Intent intent = getIntent();
-    if ("android.intent.action.VIEW".equals(intent.getAction()) && !commandLineRun) {
-      boolean loopback = intent.getBooleanExtra(CallActivity.EXTRA_LOOPBACK, false);
-      int runTimeMs = intent.getIntExtra(CallActivity.EXTRA_RUNTIME, 0);
-      boolean useValuesFromIntent =
-          intent.getBooleanExtra(CallActivity.EXTRA_USE_VALUES_FROM_INTENT, false);
-      String room = sharedPref.getString(keyprefRoom, "");
-      connectToRoom(room, true, loopback, useValuesFromIntent, runTimeMs);
-    }
-  }
-
-  @TargetApi(Build.VERSION_CODES.M)
-  private void requestPermissions() {
-    if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M) {
-      // Dynamic permissions are not required before Android M.
-      onPermissionsGranted();
-      return;
-    }
-
-    String[] missingPermissions = getMissingPermissions();
-    if (missingPermissions.length != 0) {
-      requestPermissions(missingPermissions, PERMISSION_REQUEST);
-    } else {
-      onPermissionsGranted();
-    }
-  }
-
-  @TargetApi(Build.VERSION_CODES.M)
-  private String[] getMissingPermissions() {
-    if (Build.VERSION.SDK_INT < Build.VERSION_CODES.M) {
-      return new String[0];
-    }
-
-    PackageInfo info;
-    try {
-      info = getPackageManager().getPackageInfo(getPackageName(), PackageManager.GET_PERMISSIONS);
-    } catch (PackageManager.NameNotFoundException e) {
-      Log.w(TAG, "Failed to retrieve permissions.");
-      return new String[0];
-    }
-
-    if (info.requestedPermissions == null) {
-      Log.w(TAG, "No requested permissions.");
-      return new String[0];
-    }
-
-    ArrayList<String> missingPermissions = new ArrayList<>();
-    for (int i = 0; i < info.requestedPermissions.length; i++) {
-      if (Manifest.permission.CAPTURE_VIDEO_OUTPUT.equals(info.requestedPermissions[i])) {
-        // Screen recording permission has to be asked every time a session is started. (See
-        // CallActivity#startScreenCapture.)
-        continue;
-      }
-
-      if ((info.requestedPermissionsFlags[i] & PackageInfo.REQUESTED_PERMISSION_GRANTED) == 0) {
-        missingPermissions.add(info.requestedPermissions[i]);
-      }
-    }
-    Log.d(TAG, "Missing permissions: " + missingPermissions);
-
-    return missingPermissions.toArray(new String[missingPermissions.size()]);
-  }
-
   /**
    * Get a value from the shared preference or from the intent, if it does not
    * exist the default is used.