Warnings during build

[César Ferreira]

Since I added amplitude_flutter I get these warnings while building:

Note: /Users/cesar/development/flutter/.pub-cache/hosted/pub.dartlang.org/device_info-0.4.1+5/android/src/main/java/io/flutter/plugins/deviceinfo/DeviceInfoPlugin.java uses or overrides a deprecated API.
Note: Recompile with -Xlint:deprecation for details.
Note: /Users/cesar/development/flutter/.pub-cache/hosted/pub.dartlang.org/package_info-0.4.0+14/android/src/main/java/io/flutter/plugins/packageinfo/PackageInfoPlugin.java uses or overrides a deprecated API.
Note: Recompile with -Xlint:deprecation for details.
/Users/cesar/development/flutter/.pub-cache/hosted/pub.dartlang.org/shared_preferences-0.5.6+2/android/src/main/java/io/flutter/plugins/sharedpreferences/SharedPreferencesPlugin.java:25: warning: [deprecation] getFlutterEngine() in FlutterPluginBinding has been deprecated
    setupChannel(binding.getFlutterEngine().getDartExecutor(), binding.getApplicationContext());
                        ^
1 warning
Note: /Users/cesar/development/flutter/.pub-cache/hosted/pub.dartlang.org/amplitude_flutter-1.2.0/android/src/main/java/com/amplitude/amplitude_flutter/AmplitudeFlutterPlugin.java uses unchecked or unsafe operations.

[Hao Liu]

Looks like 2 of them are from the plugin we're using.

[Viktor Morin]

AmplitudeFlutterPlugin.java uses unchecked or unsafe operations