service2.js: Move abortController management upstream

Generally, any gramar checking will be cancellable and will need this.

service2.js

@@ -41,6 +41,7 @@ class BesService {
    * Unregisters grammar checking service.
    */
   unregister() {
+    if (this.abortController) this.abortController.abort()
     besServices = besServices.filter(item => item !== this)
     this.hostElement.removeEventListener('scroll', this.onScroll)
     this.hostElement.spellcheck = this.originalSpellcheck
@@ -55,6 +56,7 @@ class BesService {
     this.proofingError = null // The first non-fatal error in grammar-checking run
     this.proofingMatches = 0 // Number of grammar mistakes detected in entire grammar-checking run
     this.updateStatusIcon('bes-status-loading', 'Besana preverja pravopis.')
+    this.abortController = new AbortController()
   }
 
   /**
@@ -72,6 +74,7 @@ class BesService {
    * @param {Response} response HTTP response
    */
   onFailedProofing(response) {
+    delete this.abortController
     this.updateStatusIcon(
       'bes-status-error',
       `Pri preverjanju pravopisa je prišlo do napake ${response.status} ${response.statusText}.`
@@ -102,6 +105,7 @@ class BesService {
    * Called when grammar-checking run is ended
    */
   onEndProofing() {
+    delete this.abortController
     if (this.proofingError) {
       this.updateStatusIcon(
         'bes-status-error',
@@ -264,38 +268,9 @@ class BesDOMService extends BesService {
     this.hostElement.removeEventListener('input', this.onInput)
     this.hostElement.removeEventListener('beforeinput', this.onBeforeInput)
     if (this.timer) clearTimeout(this.timer)
-    if (this.abortController) this.abortController.abort()
     super.unregister()
   }
 
-  /**
-   * Called initially when grammar-checking run is started
-   */
-  onStartProofing() {
-    super.onStartProofing()
-    this.abortController = new AbortController()
-  }
-
-  /**
-   * Called when grammar-checking failed (as 500 Internal server error, timeout, etc.)
-   *
-   * This error is fatal and proofing will not continue.
-   *
-   * @param {Response} response HTTP response
-   */
-  onFailedProofing(response) {
-    delete this.abortController
-    super.onFailedProofing(response)
-  }
-
-  /**
-   * Called when grammar-checking run is ended
-   */
-  onEndProofing() {
-    delete this.abortController
-    super.onEndProofing()
-  }
-
   /**
    * Called to report scrolling
    */