Revert "Android embedding refactor pr3 add remaining systemchannels (#…

…7738)" (#7849)

From build log:
```
../../flutter/shell/platform/android/io/flutter/view/FlutterView.java:95: error: cannot find symbol
    private final LocalizationChannel localizationChannel;
                  ^
  symbol:   class LocalizationChannel
  location: class FlutterView
../../flutter/shell/platform/android/io/flutter/view/FlutterView.java:172: error: cannot find symbol
        localizationChannel = new LocalizationChannel(dartExecutor);
                                  ^
  symbol:   class LocalizationChannel
  location: class FlutterView
2 errors
```

This reverts commit 256db4b.

ci/licenses_golden/licenses_flutter

@@ -450,15 +450,13 @@ FILE: ../../../flutter/shell/platform/android/io/flutter/embedding/engine/dart/D
 FILE: ../../../flutter/shell/platform/android/io/flutter/embedding/engine/dart/PlatformMessageHandler.java
 FILE: ../../../flutter/shell/platform/android/io/flutter/embedding/engine/renderer/FlutterRenderer.java
 FILE: ../../../flutter/shell/platform/android/io/flutter/embedding/engine/renderer/OnFirstFrameRenderedListener.java
-FILE: ../../../flutter/shell/platform/android/io/flutter/embedding/engine/systemchannels/AccessibilityChannel.java
 FILE: ../../../flutter/shell/platform/android/io/flutter/embedding/engine/systemchannels/KeyEventChannel.java
 FILE: ../../../flutter/shell/platform/android/io/flutter/embedding/engine/systemchannels/LifecycleChannel.java
 FILE: ../../../flutter/shell/platform/android/io/flutter/embedding/engine/systemchannels/LocalizationChannel.java
 FILE: ../../../flutter/shell/platform/android/io/flutter/embedding/engine/systemchannels/NavigationChannel.java
 FILE: ../../../flutter/shell/platform/android/io/flutter/embedding/engine/systemchannels/PlatformChannel.java
 FILE: ../../../flutter/shell/platform/android/io/flutter/embedding/engine/systemchannels/SettingsChannel.java
 FILE: ../../../flutter/shell/platform/android/io/flutter/embedding/engine/systemchannels/SystemChannel.java
-FILE: ../../../flutter/shell/platform/android/io/flutter/embedding/engine/systemchannels/TextInputChannel.java
 FILE: ../../../flutter/shell/platform/android/io/flutter/plugin/common/ActivityLifecycleListener.java
 FILE: ../../../flutter/shell/platform/android/io/flutter/plugin/common/BasicMessageChannel.java
 FILE: ../../../flutter/shell/platform/android/io/flutter/plugin/common/BinaryCodec.java

shell/platform/android/BUILD.gn

@@ -114,15 +114,13 @@ java_library("flutter_shell_java") {
     "io/flutter/embedding/engine/dart/PlatformMessageHandler.java",
     "io/flutter/embedding/engine/renderer/FlutterRenderer.java",
     "io/flutter/embedding/engine/renderer/OnFirstFrameRenderedListener.java",
-    "io/flutter/embedding/engine/systemchannels/AccessibilityChannel.java",
     "io/flutter/embedding/engine/systemchannels/KeyEventChannel.java",
     "io/flutter/embedding/engine/systemchannels/LifecycleChannel.java",
     "io/flutter/embedding/engine/systemchannels/LocalizationChannel.java",
     "io/flutter/embedding/engine/systemchannels/NavigationChannel.java",
     "io/flutter/embedding/engine/systemchannels/PlatformChannel.java",
     "io/flutter/embedding/engine/systemchannels/SettingsChannel.java",
     "io/flutter/embedding/engine/systemchannels/SystemChannel.java",
-    "io/flutter/embedding/engine/systemchannels/TextInputChannel.java",
     "io/flutter/plugin/common/ActivityLifecycleListener.java",
     "io/flutter/plugin/common/BasicMessageChannel.java",
     "io/flutter/plugin/common/BinaryCodec.java",

shell/platform/android/io/flutter/embedding/engine/systemchannels/LocalizationChannel.java

@@ -6,17 +6,14 @@
 
 import android.support.annotation.NonNull;
 
-import java.util.ArrayList;
 import java.util.Arrays;
-import java.util.List;
-import java.util.Locale;
 
 import io.flutter.embedding.engine.dart.DartExecutor;
 import io.flutter.plugin.common.JSONMethodCodec;
 import io.flutter.plugin.common.MethodChannel;
 
 /**
- * Sends the platform's locales to Dart.
+ * TODO(mattcarroll): fill in javadoc for LocalizationChannel.
  */
 public class LocalizationChannel {
 
@@ -27,18 +24,12 @@ public LocalizationChannel(@NonNull DartExecutor dartExecutor) {
     this.channel = new MethodChannel(dartExecutor, "flutter/localization", JSONMethodCodec.INSTANCE);
   }
 
-  /**
-   * Send the given {@code locales} to Dart.
-   */
-  public void sendLocales(List<Locale> locales) {
-    List<String> data = new ArrayList<>();
-    for (Locale locale : locales) {
-      data.add(locale.getLanguage());
-      data.add(locale.getCountry());
-      data.add(locale.getScript());
-      data.add(locale.getVariant());
-    }
-    channel.invokeMethod("setLocale", data);
+  public void setLocale(String language, String country) {
+    channel.invokeMethod("setLocale", Arrays.asList(language, country));
+  }
+
+  public void setMethodCallHandler(MethodChannel.MethodCallHandler handler) {
+    channel.setMethodCallHandler(handler);
   }
 
 }