Fix some more Kotlin warnings

Author: pimterry

app/src/main/java/tech/httptoolkit/android/HttpToolkitApplication.kt

@@ -124,7 +124,7 @@ class HttpToolkitApplication : Application() {
         // Get & return the actual referrer and return it
         Log.i(TAG, "Getting first run referrer...")
         return suspendCoroutine { cont ->
-            var wasResumed = AtomicBoolean()
+            val wasResumed = AtomicBoolean()
             val resume = { value: String? ->
                 if (wasResumed.getAndSet(true)) {
                     cont.resume(value)

app/src/main/java/tech/httptoolkit/android/ProxyVpnService.kt

@@ -98,7 +98,7 @@ class ProxyVpnService : VpnService(), IProtectSocket {
 
     override fun onRevoke() {
         super.onRevoke()
-        app!!.trackEvent("VPN", "vpn-revoked")
+        app.trackEvent("VPN", "vpn-revoked")
         Log.i(TAG, "onRevoke called")
         stopVpn()
     }
@@ -151,8 +151,8 @@ class ProxyVpnService : VpnService(), IProtectSocket {
 
         if (this.vpnInterface != null) return false // The VPN is already running, somehow? Do nothing
 
-        app!!.pauseEvents() // Try not to send events while the VPN is active, it's unnecessary noise
-        app!!.trackEvent("VPN", "vpn-started")
+        app.pauseEvents() // Try not to send events while the VPN is active, it's unnecessary noise
+        app.trackEvent("VPN", "vpn-started")
         val vpnInterface = Builder()
             .addAddress(VPN_IP_ADDRESS, 32)
             .addRoute(ALL_ROUTES, 0)
@@ -225,8 +225,8 @@ class ProxyVpnService : VpnService(), IProtectSocket {
         Log.i(TAG, "VPN stopping..")
 
         if (vpnRunnable != null) {
-            app!!.trackEvent("VPN", "vpn-stopped")
-            app!!.resumeEvents()
+            app.trackEvent("VPN", "vpn-stopped")
+            app.resumeEvents()
 
             vpnRunnable!!.stop()
             vpnRunnable = null