Clear adb logcat when clearing Flipper logs

Summary: When using "Clear logs" in Flipper, also flush the native Android buffer.

Reviewed By: jknoxville

Differential Revision: D14225722

fbshipit-source-id: f41ff9013b95fc3271d3ae44910da18023708d2d

src/devices/AndroidDevice.js

@@ -9,6 +9,7 @@ import type {DeviceType, DeviceShell} from './BaseDevice.js';
 
 import {Priority} from 'adbkit-logcat-fb';
 import child_process from 'child_process';
+import child_process_promise from 'child-process-es6-promise';
 import BaseDevice from './BaseDevice.js';
 
 type ADBClient = any;
@@ -80,4 +81,8 @@ export default class AndroidDevice extends BaseDevice {
   spawnShell(): ?DeviceShell {
     return child_process.spawn('adb', ['-s', this.serial, 'shell', '-t', '-t']);
   }
+
+  clearLogs(): Promise<void> {
+    return child_process_promise.spawn('adb', ['logcat', '-c']);
+  }
 }