Fix high pkd CPU usage issue

Summary:
Running `instruments -s devices` causes the `pkd` process in catalina to spike to ~100% for a few seconds.

Flipper runs this command every 3 seconds to poll for devices.
This switches it to use `idb list-targets` instead which is much more performant.

Currently switched off in the open-source version while we make sure it's working well. If you set the GK value 'flipper_use_idb_to_list_devices' to true, then you'll get the new behaviour.

Reviewed By: passy

Differential Revision: D23102067

fbshipit-source-id: 9e17155d938a4fe326e082511f747444e4b533a2

desktop/app/src/utils/CertificateProvider.tsx

@@ -342,28 +342,30 @@ export default class CertificateProvider {
       // It's a simulator, the deviceId is in the filepath.
       return Promise.resolve(matches[1]);
     }
-    return iosUtil.targets().then((targets) => {
-      if (targets.length === 0) {
-        throw new Error('No iOS devices found');
-      }
-      const deviceMatchList = targets.map((target) =>
-        this.iOSDeviceHasMatchingCSR(
-          deviceCsrFilePath,
-          target.udid,
-          appName,
-          csr,
-        ).then((isMatch) => {
-          return {id: target.udid, isMatch};
-        }),
-      );
-      return Promise.all(deviceMatchList).then((devices) => {
-        const matchingIds = devices.filter((m) => m.isMatch).map((m) => m.id);
-        if (matchingIds.length == 0) {
-          throw new Error(`No matching device found for app: ${appName}`);
+    return iosUtil
+      .targets(this.store.getState().settingsState.idbPath)
+      .then((targets) => {
+        if (targets.length === 0) {
+          throw new Error('No iOS devices found');
         }
-        return matchingIds[0];
+        const deviceMatchList = targets.map((target) =>
+          this.iOSDeviceHasMatchingCSR(
+            deviceCsrFilePath,
+            target.udid,
+            appName,
+            csr,
+          ).then((isMatch) => {
+            return {id: target.udid, isMatch};
+          }),
+        );
+        return Promise.all(deviceMatchList).then((devices) => {
+          const matchingIds = devices.filter((m) => m.isMatch).map((m) => m.id);
+          if (matchingIds.length == 0) {
+            throw new Error(`No matching device found for app: ${appName}`);
+          }
+          return matchingIds[0];
+        });
       });
-    });
   }
 
   androidDeviceHasMatchingCSR(