Prevent Long Cell Names from Obscuring Cancel and Save Buttons (#1805)

* Prevent cell renamer from pushing controls off the screen

* Only enforce width proportions on page headers if a center element is provided

ui/src/dashboards/components/rename_dashboard/RenameDashboard.scss

@@ -7,8 +7,8 @@ $rename-dash-title-padding: 8px;
 
 .rename-dashboard {
   height: $form-sm-height;
-  min-width: 0;
   width: 100%;
+  max-width: 42vw;
 }
 
 .rename-dashboard--title,

ui/src/pageLayout/components/Page.scss

@@ -46,7 +46,6 @@
 }
 
 .page-header--left {
-  flex: 1 0 0;
   justify-content: flex-start;
   > * {
     margin: 0 4px 0 0;

ui/src/pageLayout/components/PageHeaderLeft.tsx

@@ -44,9 +44,7 @@ class PageHeaderLeft extends Component<Props> {
     const {offsetPixels} = this.props
 
     if (offsetPixels === DEFAULT_OFFSET) {
-      return {
-        flex: `1 0 ${offsetPixels}`,
-      }
+      return
     }
 
     return {

ui/src/pageLayout/components/PageHeaderRight.tsx

@@ -32,9 +32,7 @@ class PageHeaderRight extends Component<Props> {
     const {offsetPixels} = this.props
 
     if (offsetPixels === DEFAULT_OFFSET) {
-      return {
-        flex: `1 0 ${offsetPixels}`,
-      }
+      return
     }
 
     return {