DevTools: fix regressed Object popovers, dark theme context

Fixes 2 recent regressions
- Object popover properties had extra scrollbars; now they have
  standard line-height and show overflow
- Dark theme forced SoftContextMenus, which appear behind the
  inspected page in DeviceMode; now they are not enforced by theme

Screenshots:
https://imgur.com/a/JOXwaGI
https://imgur.com/a/NmXVtyx

Bug: none
Change-Id: Ia79e2a23ea987f4ed9e2cd29ba02537bdd4db076
Reviewed-on: https://chromium-review.googlesource.com/1167887Reviewed-by: Andrey Lushnikov <lushnikov@chromium.org>
Commit-Queue: Erik Luo <luoe@chromium.org>
Cr-Commit-Position: refs/heads/master@{#581816}

third_party/blink/renderer/devtools/front_end/object_ui/ObjectPopoverHelper.js

@@ -71,7 +71,8 @@ ObjectUI.ObjectPopoverHelper = class {
         const titleElement = popoverContentElement.createChild('div', 'monospace object-popover-title');
         titleElement.createChild('span').textContent = description;
         linkifier = new Components.Linkifier();
-        const section = new ObjectUI.ObjectPropertiesSection(result, '', linkifier);
+        const section = new ObjectUI.ObjectPropertiesSection(
+            result, '', linkifier, undefined, undefined, undefined, true /* showOverflow */);
         section.element.classList.add('object-popover-tree');
         section.titleLessMode();
         popoverContentElement.appendChild(section.element);

third_party/blink/renderer/devtools/front_end/object_ui/objectPropertiesSection.css

@@ -54,6 +54,7 @@
 .name-and-value {
     overflow-x: hidden;
     text-overflow: ellipsis;
+    line-height: normal;
 }
 
 .editing-sub-part .name-and-value {

third_party/blink/renderer/devtools/front_end/ui/ContextMenu.js

@@ -434,8 +434,7 @@ UI.ContextMenu = class extends UI.ContextSubMenu {
 
   _innerShow() {
     const menuObject = this._buildMenuDescriptors();
-    if (this._useSoftMenu || UI.ContextMenu._useSoftMenu || InspectorFrontendHost.isHostedMode() ||
-        (UI.themeSupport.hasTheme() && menuObject.length)) {
+    if (this._useSoftMenu || UI.ContextMenu._useSoftMenu || InspectorFrontendHost.isHostedMode()) {
       this._softMenu = new UI.SoftContextMenu(menuObject, this._itemSelected.bind(this));
       this._softMenu.show(this._event.target.ownerDocument, new AnchorBox(this._x, this._y, 0, 0));
     } else {