MM-13321: Fix providers that don't extend Provider. (#2139)

* Fix providers that don't extend Provider.

* Fix snapshots

components/__snapshots__/textbox.test.jsx.snap

@@ -57,7 +57,12 @@ exports[`components/TextBox should match snapshot with required props 1`] = `
           "latestPrefix": "",
           "requestStarted": false,
         },
-        EmoticonProvider {},
+        EmoticonProvider {
+          "disableDispatches": false,
+          "latestComplete": true,
+          "latestPrefix": "",
+          "requestStarted": false,
+        },
       ]
     }
     renderDividers={true}
@@ -207,7 +212,12 @@ exports[`components/TextBox should throw error when new property is too long 1`]
           "latestPrefix": "",
           "requestStarted": false,
         },
-        EmoticonProvider {},
+        EmoticonProvider {
+          "disableDispatches": false,
+          "latestComplete": true,
+          "latestPrefix": "",
+          "requestStarted": false,
+        },
       ]
     }
     renderDividers={true}
@@ -357,7 +367,12 @@ exports[`components/TextBox should throw error when value is too long 1`] = `
           "latestPrefix": "",
           "requestStarted": false,
         },
-        EmoticonProvider {},
+        EmoticonProvider {
+          "disableDispatches": false,
+          "latestComplete": true,
+          "latestPrefix": "",
+          "requestStarted": false,
+        },
       ]
     }
     renderDividers={true}

components/suggestion/command_provider.jsx

@@ -11,6 +11,7 @@ import store from 'stores/redux_store.jsx';
 import * as UserAgent from 'utils/user_agent.jsx';
 
 import Suggestion from './suggestion.jsx';
+import Provider from './provider.jsx';
 
 export class CommandSuggestion extends Suggestion {
     render() {
@@ -38,7 +39,7 @@ export class CommandSuggestion extends Suggestion {
     }
 }
 
-export default class CommandProvider {
+export default class CommandProvider extends Provider {
     handlePretextChanged(pretext, resultCallback) {
         if (pretext.startsWith('/')) {
             const command = pretext.toLowerCase();

components/suggestion/emoticon_provider.jsx

@@ -13,6 +13,7 @@ import store from 'stores/redux_store.jsx';
 import * as Emoticons from 'utils/emoticons.jsx';
 
 import Suggestion from './suggestion.jsx';
+import Provider from './provider.jsx';
 
 const MIN_EMOTICON_LENGTH = 2;
 const EMOJI_CATEGORY_SUGGESTION_BLACKLIST = ['skintone'];
@@ -49,7 +50,7 @@ class EmoticonSuggestion extends Suggestion {
     }
 }
 
-export default class EmoticonProvider {
+export default class EmoticonProvider extends Provider {
     handlePretextChanged(pretext, resultsCallback) {
         // Look for the potential emoticons at the start of the text, after whitespace, and at the start of emoji reaction commands
         const captured = (/(^|\s|^\+|^-)(:([^:\s]*))$/g).exec(pretext);