Update Assistant settings style

- Hide voice model settings if activity control state is false.
- Add a min-width to the DspState select box.

Bug: b/124246347, b/123376071
Change-Id: Ie025778aaf3173a9c8cb3fa56f0b6aff143d1704
Reviewed-on: https://chromium-review.googlesource.com/c/1464436
Commit-Queue: Yue Li <updowndota@chromium.org>
Reviewed-by: Steven Bennetts <stevenjb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#631920}

chrome/browser/resources/settings/google_assistant_page/google_assistant_page.html

@@ -14,7 +14,15 @@
 
 <dom-module id="settings-google-assistant-page">
   <template>
-    <style include="settings-shared md-select"></style>
+    <style include="settings-shared md-select">
+      .text-area {
+        margin-inline-end: 24px;
+      }
+
+      select.md-select {
+        min-width: 200px;
+      }
+    </style>
     <settings-toggle-button id="googleAssistantEnable"
         class="first primary-toggle"
         pref="{{prefs.settings.voice_interaction.enabled}}"
@@ -59,7 +67,7 @@
             </template>
           </select>
         </div>
-        <template is="dom-if" if="[[voiceMatchEnabled_]]">
+        <template is="dom-if" if="[[shouldShowVoiceMatchSettings_]]">
           <div class="settings-box two-line">
             <div class="start text-area">
               <div class="label">

chrome/browser/resources/settings/google_assistant_page/google_assistant_page.js

@@ -31,7 +31,7 @@ Polymer({
     },
 
     /** @private */
-    voiceMatchEnabled_: {
+    shouldShowVoiceMatchSettings_: {
       type: Boolean,
       value: false,
     },
@@ -150,8 +150,11 @@ Polymer({
   onPrefsChanged_: function() {
     this.refreshDspHotwordState_();
 
-    this.voiceMatchEnabled_ = loadTimeData.getBoolean('voiceMatchEnabled') &&
-        this.getPref('settings.voice_interaction.hotword.enabled.value');
+    this.shouldShowVoiceMatchSettings_ =
+        loadTimeData.getBoolean('voiceMatchEnabled') &&
+        this.getPref('settings.voice_interaction.hotword.enabled.value') &&
+        this.getPref(
+            'settings.voice_interaction.activity_control.accepted.value');
   },
 
   /** @private */