DevTools: Initial implementation of line-level CPU profile.

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-profile-info {
+  width: 74px;
+  background-color: white;
+  margin-left: 3px;
+}
+
+.CodeMirror-profile-line-info {
+  text-align: right;
+  padding-right: 3px;
+}
+
 .CodeMirror .source-frame-eval-expression {
   outline: 0;
   border: 1px solid rgb(163, 41, 34);
   border-left-width: 0;
   border-right-width: 0;
   background-color: rgb(255, 255, 194);
 }
 
 .CodeMirror .source-frame-eval-expression-end {
   border-right-width: 1px;
@@ skipping 313 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;
 }