MD Extensions: fix error-console sub-page looking broken.

This CL is the first pass for error-console such that it no longer looks
completely broken, as well as fixing keyboard navigation. There will be 
follow-up CLs to bring it closer to the design spec as well as adding the
missing dev-tool buttons.

Bug: 768580
Cq-Include-Trybots: master.tryserver.chromium.linux:closure_compilation
Change-Id: I15d85e0ebe946b11a9a7aaf9f471ba22fe705a97
Reviewed-on: https://chromium-review.googlesource.com/685988
Commit-Queue: Scott Chen <scottchen@chromium.org>
Reviewed-by: Demetrios Papadopoulos <dpapad@chromium.org>
Cr-Commit-Position: refs/heads/master@{#505257}

chrome/browser/resources/md_extensions/code_section.html

@@ -12,6 +12,7 @@
         color: var(--paper-grey-800);
         display: flex;
         font-family: monospace;
+        overflow: auto;
         white-space: pre;
       }
 

chrome/browser/resources/md_extensions/error_page.html

@@ -14,22 +14,35 @@
 <dom-module id="extensions-error-page">
   <template>
     <style include="cr-icons cr-hidden-style">
+      :host {
+        display: block;
+        height: 100%;
+        overflow: auto;
+      }
+
       #main {
         background-color: white;
-        height: 800px;
-        width: 90%;
+        display: flex;
+        flex-direction: column;
+        margin: auto;
+        min-height: 100%;
+        width: 640px;
       }
 
       #heading {
-        color: var(--paper-grey-600);
         height: 40px;
         margin-bottom: 30px;
         padding: 8px 12px 0;
+        @apply(--cr-title-text);
       }
 
       #errors-list {
         min-height: 100px;
-        padding: 0 10px;
+        padding: 0 var(--cr-section-padding);
+      }
+
+      #content-view {
+        padding: 0 var(--cr-section-padding);
       }
 
       .error-item {
@@ -39,6 +52,10 @@
         margin: 5px 0;
       }
 
+      .error-item button[is='paper-icon-button-light'] {
+        -webkit-margin-end: 0;
+      }
+
       .error-item.selected {
         background-color: #ccc;
       }
@@ -68,16 +85,18 @@
         </button>
         <span>$i18n{errorsPageHeading}</span>
       </div>
-      <iron-list id="errors-list" items="[[calculateShownItems_(data.*)]]">
+      <iron-list id="errors-list" items="[[calculateShownItems_(data.*)]]"
+          preserve-focus>
         <template>
-          <div class$="[[computeErrorClass_(selectedError_, item)]]"
+          <div class$="error-item [[computeErrorClass_(selectedError_, item)]]"
               error="[[item]]"
               tabindex$="[[tabIndex]]"
-              on-tap="onErrorItemTap_" on-keydown="onErrorItemKeydown_">
+              on-tap="onErrorItemAction_" on-keydown="onErrorItemAction_">
             <img class$="[[computeErrorIconClass_(item)]]">
             <div class="error-message">[[item.message]]</div>
             <button is="paper-icon-button-light" class="icon-delete-gray"
-                on-tap="onDeleteErrorTap_" tabindex$="[[tabIndex]]"></button>
+                on-tap="onDeleteErrorAction_" tabindex$="[[tabIndex]]"
+                on-keydown="onDeleteErrorAction_"></button>
           </div>
         </template>
       </iron-list>

chrome/browser/resources/md_extensions/error_page.js

@@ -64,6 +64,8 @@ cr.define('extensions', function() {
      * @private
      */
     calculateShownItems_: function() {
+      // Render iron-list correctly after data changes.
+      setTimeout(() => this.$['errors-list'].fire('iron-resize'));
       return this.data.manifestErrors.concat(this.data.runtimeErrors);
     },
 
@@ -98,14 +100,16 @@ cr.define('extensions', function() {
     },
 
     /**
-     * @param {!Event} event
+     * @param {!Event} e
      * @private
      */
-    onDeleteErrorTap_: function(event) {
-      // TODO(devlin): It would be cleaner if we could cast this to a
-      // PolymerDomRepeatEvent-type thing, but that doesn't exist yet.
-      const e = /** @type {!{model:Object}} */ (event);
-      this.delegate.deleteErrors(this.data.id, [e.model.item.id]);
+    onDeleteErrorAction_: function(e) {
+      if (e.type == 'keydown' && !((e.code == 'Space' || e.code == 'Enter')))
+        return;
+
+      this.delegate.deleteErrors(
+          this.data.id, [(/** @type {!{model:Object}} */ (e)).model.item.id]);
+      e.stopPropagation();
     },
 
     /**
@@ -146,7 +150,7 @@ cr.define('extensions', function() {
      * @private
      */
     computeErrorClass_: function(selectedError, error) {
-      return selectedError == error ? 'error-item selected' : 'error-item';
+      return selectedError == error ? 'selected' : '';
     },
 
     /**
@@ -162,17 +166,11 @@ cr.define('extensions', function() {
      * @param {!{model: !{item: (!RuntimeError|!ManifestError)}}} e
      * @private
      */
-    onErrorItemTap_: function(e) {
-      this.selectError_(e.model.item);
-    },
+    onErrorItemAction_: function(e) {
+      if (e.type == 'keydown' && !((e.code == 'Space' || e.code == 'Enter')))
+        return;
 
-    /**
-     * @param {!{model: !{item: (!RuntimeError|!ManifestError)}}} e
-     * @private
-     */
-    onErrorItemKeydown_: function(e) {
-      if (e.key == ' ' || e.key == 'Enter')
-        this.selectError_(e.model.item);
+      this.selectError_(e.model.item);
     },
   });