support reboot parameter for android

If reboot option activated, it will always wipe data of emulator on start, and close emulator at the end,
It also use device name and platform version to create avd name, if it is not defined.

Author: alizelzele

lib/driver.js

@@ -107,6 +107,11 @@ class AndroidDriver extends BaseDriver {
         this.jwpProxyAvoid.push(['GET', new RegExp('^/session/[^/]+/screenshot')]);
       }
 
+      if (this.opts.reboot) {
+        this.setAvdFromCapabilities(caps);
+        this.addWipeDataToAvdArgs();
+      }
+
       // get device udid for this session
       let {udid, emPort} = await helpers.getDeviceInfoFromCaps(this.opts);
       this.opts.udid = udid;
@@ -143,6 +148,29 @@ class AndroidDriver extends BaseDriver {
     }
   }
 
+  setAvdFromCapabilities (caps) {
+    if (this.opts.avd) {
+      log.info('avd name defined, ignoring device name and platform version');
+    } else {
+      if (!caps.deviceName) {
+        log.errorAndThrow('avd or deviceName should be specified when reboot option is enables');
+      }
+      if (!caps.platformVersion) {
+        log.errorAndThrow('avd or platformVersion should be specified when reboot option is enabled');
+      }
+      let avdDevice = caps.deviceName.replace(/[^a-zA-Z0-9_.]/g, "-");
+      this.opts.avd = `${avdDevice}__${caps.platformVersion}`;
+    }
+  }
+
+  addWipeDataToAvdArgs () {
+    if (!this.opts.avdArgs) {
+      this.opts.avdArgs = '-wipe-data';
+    } else  if (this.opts.avdArgs.toLowerCase().indexOf("-wipe-data") === -1) {
+      this.opts.avdArgs += ' -wipe-data';
+    }
+  }
+
   get appOnDevice () {
     return this.helpers.isPackageOrBundle(this.opts.app) || (!this.opts.app &&
            this.helpers.isPackageOrBundle(this.opts.appPackage));
@@ -312,6 +340,11 @@ class AndroidDriver extends BaseDriver {
         await this.adb.uninstallApk(this.opts.appPackage);
       }
       await this.bootstrap.shutdown();
+      if (this.opts.reboot) {
+        let avdName = this.opts.avd.replace('@', '');
+        log.debug(`closing emulator '${avdName}'`);
+        this.adb.killEmulator(avdName);
+      }
       this.bootstrap = null;
     } else {
       log.debug("Called deleteSession but bootstrap wasn't active");