DevTools: follow up to r361550, fix the color picker background and allow for themed stylesheet mar…

third_party/WebKit/Source/devtools/front_end/elements/spectrum.css

 /* https://github.com/bgrins/spectrum */
 :host {
     width: 232px;
     height: 240px;
     -webkit-user-select: none;
 }
 
 :host(.palettes-enabled) {
     height: 319px;
 }
@@ skipping 33 matching lines @@
     width: 130px;
     height: 11px;
     border-radius: 2px;
 }
 
 .spectrum-dragger,
 .spectrum-slider {
     -webkit-user-select: none;
 }
 
-.spectrum-sat {
+.spectrum-sat,
+.-theme-preserve {
     background-image: linear-gradient(to right, white, rgba(204, 154, 129, 0));
 }
 
-.spectrum-val {
+.spectrum-val,
+.-theme-preserve {
     background-image: linear-gradient(to top, black, rgba(204, 154, 129, 0));
 }
 
 .spectrum-hue {
     background: linear-gradient(to left, #ff0000 0%, #ffff00 17%, #00ff00 33%, #00ffff 50%, #0000ff 67%, #ff00ff 83%, #ff0000 100%);
 }
 
 .spectrum-dragger {
     border-radius: 12px;
     height: 12px;
@@ skipping 316 matching lines @@
 
 .delete-color-toolbar.dragging {
     visibility: visible;
     animation: showDeleteToolbar 100ms 150ms cubic-bezier(0, 0, 0.2, 1) backwards;
 }
 
 .delete-color-toolbar-active {
     background-color: #ddd;
     color: white;
 }