Fix emulator usage on linux

Summary: emulator isn't on the path in CI machines, but we already have ANDROID_HOME set so we can work out where it is.

Reviewed By: danielbuechele

Differential Revision: D15080422

fbshipit-source-id: 2c50a3de27909d2bfc82ea0210d06a0cc32357d7

src/chrome/DevicesButton.js

@@ -40,6 +40,7 @@ class DevicesButton extends Component<Props> {
     // On Linux, you must run the emulator from the directory it's in because
     // reasons ...
     whichPromise('emulator')
+      .catch(e => `${process.env.ANDROID_HOME || ''}/tools/emulator`)
       .then(emulatorPath => {
         const child = spawn(emulatorPath, [`@${name}`], {
           detached: true,

src/dispatcher/androidDevice.js

@@ -64,22 +64,24 @@ function getRunningEmulatorName(id: string): Promise<?string> {
 export default (store: Store, logger: Logger) => {
   const watchAndroidDevices = () => {
     // get emulators
-    promisify(which)('emulator').then(emulatorPath => {
-      child_process.exec(
-        `${emulatorPath} -list-avds`,
-        (error: ?Error, data: ?string) => {
-          if (error != null || data == null) {
-            console.error(error || 'Failed to list AVDs');
-            return;
-          }
-          const payload = data.split('\n').filter(Boolean);
-          store.dispatch({
-            type: 'REGISTER_ANDROID_EMULATORS',
-            payload,
-          });
-        },
-      );
-    });
+    promisify(which)('emulator')
+      .catch(e => `${process.env.ANDROID_HOME || ''}/tools/emulator`)
+      .then(emulatorPath => {
+        child_process.exec(
+          `${emulatorPath} -list-avds`,
+          (error: ?Error, data: ?string) => {
+            if (error != null || data == null) {
+              console.error(error || 'Failed to list AVDs');
+              return;
+            }
+            const payload = data.split('\n').filter(Boolean);
+            store.dispatch({
+              type: 'REGISTER_ANDROID_EMULATORS',
+              payload,
+            });
+          },
+        );
+      });
 
     getAdbClient()
       .then(client => {