Add setting to expand inline diff (frontend)

Adds a setting to general preferences in the frontend. Will be followed
by a change that actually changes the file list based on this
preference.

Feature: Issue 5115
Change-Id: I35db6651161259e9d308c75f0b67332083757a84

polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-view.html

@@ -183,6 +183,16 @@ limitations under the License.
               </select>
             </span>
           </section>
+          <section>
+            <span class="title">Expand Inline Diffs</span>
+            <span class="value">
+              <input
+                  id="expandInlineDiffs"
+                  type="checkbox"
+                  checked$="[[_localPrefs.expand_inline_diffs]]"
+                  on-change="_handleExpandInlineDiffsChanged">
+            </span>
+          </section>
           <gr-button
               id="savePrefs"
               on-tap="_handleSavePreferences"

polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-view.js

@@ -20,6 +20,7 @@
     'time_format',
     'email_strategy',
     'diff_view',
+    'expand_inline_diffs',
   ];
 
   Polymer({
@@ -228,6 +229,11 @@
       this._diffPrefsChanged = true;
     },
 
+    _handleExpandInlineDiffsChanged: function() {
+      this.set('_localPrefs.expand_inline_diffs',
+          this.$.expandInlineDiffs.checked);
+    },
+
     _handleMenuChanged: function() {
       if (this._isLoading()) { return; }
       this._menuChanged = true;

polygerrit-ui/app/elements/settings/gr-settings-view/gr-settings-view_test.html

@@ -159,6 +159,8 @@ limitations under the License.
           .firstElementChild.bindValue, preferences.email_strategy);
       assert.equal(valueOf('Diff View', 'preferences')
           .firstElementChild.bindValue, preferences.diff_view);
+      assert.equal(valueOf('Expand Inline Diffs', 'preferences')
+          .firstElementChild.checked, false);
 
       assert.isFalse(element._prefsChanged);
       assert.isFalse(element._menuChanged);
@@ -166,8 +168,13 @@ limitations under the License.
       // Change the diff view element.
       var diffSelect = valueOf('Diff View', 'preferences').firstElementChild;
       diffSelect.bindValue = 'SIDE_BY_SIDE';
+
+      var expandInlineDiffs =
+          valueOf('Expand Inline Diffs', 'preferences').firstElementChild;
       diffSelect.fire('change');
 
+      MockInteractions.tap(expandInlineDiffs);
+
       assert.isTrue(element._prefsChanged);
       assert.isFalse(element._menuChanged);
 
@@ -175,6 +182,7 @@ limitations under the License.
         savePreferences: function(prefs) {
           assert.equal(prefs.diff_view, 'SIDE_BY_SIDE');
           assertMenusEqual(prefs.my, preferences.my);
+          assert.equal(prefs.expand_inline_diffs, true);
           return Promise.resolve();
         }
       });