Finish CSS cleanup.

packages/notebook/src/truststatus.tsx

@@ -21,21 +21,21 @@ function cellTrust(
       `Notebook trusted: ${props.trustedCells} of ${
         props.totalCells
       } cells trusted.`,
-      'trusted-item'
+      'jp-StatusItem-trusted'
     ];
   } else if (props.activeCellTrusted) {
     return [
       `Active cell trusted: ${props.trustedCells} of ${
         props.totalCells
       } cells trusted. `,
-      'trusted-item'
+      'jp-StatusItem-trusted'
     ];
   } else {
     return [
       `Notebook not trusted: ${props.trustedCells} of ${
         props.totalCells
       } cells trusted.`,
-      'not-trusted-item'
+      'jp-StatusItem-untrusted'
     ];
   }
 }

packages/statusbar/src/defaults/lineCol.tsx

@@ -114,7 +114,7 @@ class LineFormComponent extends React.Component<
 
             <input
               type="submit"
-              className={classes(lineFormButton, 'lineForm-enter-icon')}
+              className={classes(lineFormButton, 'jp-StatusItem-line-form')}
               value=""
             />
           </div>

packages/statusbar/src/defaults/runningSessions.tsx

@@ -34,11 +34,11 @@ function RunningSessionsComponent(
     <GroupItem spacing={HALF_SPACING} onClick={props.handleClick}>
       <GroupItem spacing={HALF_SPACING}>
         <TextItem source={props.terminals} />
-        <IconItem source={'terminal-item'} offset={{ x: 1, y: 3 }} />
+        <IconItem source={'jp-StatusItem-terminal'} offset={{ x: 1, y: 3 }} />
       </GroupItem>
       <GroupItem spacing={HALF_SPACING}>
         <TextItem source={props.kernels} />
-        <IconItem source={'kernel-item'} offset={{ x: 0, y: 2 }} />
+        <IconItem source={'jp-StatusItem-kernel'} offset={{ x: 0, y: 2 }} />
       </GroupItem>
     </GroupItem>
   );