DevTools: popover, selection and other minor theme tweaks.

third_party/WebKit/Source/devtools/front_end/source_frame/cmdevtools.css

 .CodeMirror {
   line-height: 1.2em !important;
   background-color: transparent !important;
 }
 
 .CodeMirror-linewidget {
   overflow: visible !important;
 }
 
 .CodeMirror .source-frame-eval-expression {
@@ skipping 216 matching lines @@
     border-top-right-radius: 1px;
     border-bottom-right-radius: 1px;
 }
 
 .cm-line-with-selection .cm-column-with-selection.cm-search-highlight:before {
     margin: -1px -1px -1px -1px;
     background-color: rgb(241, 234, 0);
     z-index: -1;
 }
 
+.-theme-with-dark-background .cm-line-with-selection .cm-column-with-selection.cm-search-highlight:before {
+    background-color: hsl(133, 100%, 30%);
+}
+
+.-theme-with-dark-background.cm-line-with-selection .cm-search-highlight {
+    color: #333;
+}
+
 .CodeMirror .text-editor-line-decoration {
     position: absolute;
 }
 
 .CodeMirror .text-editor-line-decoration-wave {
     position: absolute;
     top: -2px;
     cursor: pointer;
     height: 4px;
 }
@@ skipping 78 matching lines @@
     background-color: rgba(255, 0, 0, 0.05);
 }
 
 .CodeMirror-activeline .cm-trailing-whitespace {
     background-color: transparent;
 }
 
 .-theme-with-dark-background .CodeMirror .CodeMirror-selected {
     background-color: #454545;
 }