refactor(geolocation): simplify API, defer permission checks (#1773)

plugins/geolocation/README.md

@@ -87,16 +87,31 @@ fn main() {
 Afterwards all the plugin's APIs are available through the JavaScript guest bindings:
 
 ```javascript
-import { getCurrentPosition, watchPosition } from '@tauri-apps/plugin-log'
+import {
+  checkPermissions,
+  requestPermissions,
+  getCurrentPosition,
+  watchPosition
+} from '@tauri-apps/plugin-log'
 
-const pos = await getCurrentPosition()
+let permissions = await checkPermissions()
+if (
+  permissions.location === 'prompt' ||
+  permissions.location === 'prompt-with-rationale'
+) {
+  permissions = await requestPermissions(['location'])
+}
 
-await watchPosition(
-  { enableHighAccuracy: true, timeout: 10000, maximumAge: 0 },
-  (pos) => {
-    console.log(pos)
-  }
-)
+if (permissions.location === 'granted') {
+  const pos = await getCurrentPosition()
+
+  await watchPosition(
+    { enableHighAccuracy: true, timeout: 10000, maximumAge: 0 },
+    (pos) => {
+      console.log(pos)
+    }
+  )
+}
 ```
 
 ## Contributing