Fix more react warnings

Summary: Fixing random React errors as I encountered them.

Reviewed By: jknoxville

Differential Revision: D18397950

fbshipit-source-id: cb73fcd6cd9aac2cd53c982e5a58760be12a10ca

src/chrome/Popover.tsx

@@ -163,8 +163,9 @@ export default class Popover extends PureComponent<Props> {
   };
 
   render() {
-    return [
-      <Anchor src="./anchor.svg" key="anchor" />,
+    return (
+      <>
+        <Anchor src="./anchor.svg" key="anchor" />
         <PopoverContainer innerRef={this._setRef} key="popup">
           {this.props.sections.map(section => {
             if (section.items.length > 0) {
@@ -191,7 +192,8 @@ export default class Popover extends PureComponent<Props> {
               return null;
             }
           })}
-      </PopoverContainer>,
-    ];
+        </PopoverContainer>
+      </>
+    );
   }
 }

src/chrome/ShareSheetExportUrl.tsx

@@ -228,7 +228,10 @@ export default class ShareSheetExportUrl extends Component<Props, State> {
                       used to share with other Flipper users. Opening it will
                       import the data from your trace.
                     </InfoText>
-                    <Copy value={(result as DataExportResult).flipperUrl} />
+                    <Copy
+                      value={(result as DataExportResult).flipperUrl}
+                      readOnly
+                    />
                     <InfoText>
                       When sharing your Flipper link, consider that the captured
                       data might contain sensitve information like access tokens

src/ui/components/Popover.tsx

@@ -93,14 +93,17 @@ export default class Popover extends PureComponent<Props> {
   };
 
   render() {
-    return [
-      <Anchor src="./anchor.svg" key="anchor" />,
+    return (
+      <>
+        <Anchor src="./anchor.svg" key="anchor" />
         <PopoverContainer
           innerRef={this._setRef}
           key="popup"
           opts={this.props.forceOpts || {}}>
           {this.props.children}
-      </PopoverContainer>,
-    ];
+        </PopoverContainer>
+        ,
+      </>
+    );
   }
 }

src/ui/components/elements-inspector/elements.tsx

@@ -134,7 +134,6 @@ class PartialHighlight extends PureComponent<{
 
   render() {
     const {highlighted, content, selected} = this.props;
-    let renderedValue;
     if (
       content &&
       highlighted != null &&
@@ -148,19 +147,18 @@ class PartialHighlight extends PureComponent<{
       const before = content.substring(0, highlightStart);
       const match = content.substring(highlightStart, highlightEnd);
       const after = content.substring(highlightEnd);
-      renderedValue = [
+      return (
         <span>
           {before}
           <PartialHighlight.HighlightedText selected={selected}>
             {match}
           </PartialHighlight.HighlightedText>
           {after}
-        </span>,
-      ];
+        </span>
+      );
     } else {
-      renderedValue = <span>{content}</span>;
+      return <span>{content}</span>;
     }
-    return renderedValue;
   }
 }