Solve the issue where the bottom view of Sidebar was pushed down

Summary: This fixes the issue raised [here](https://fb.workplace.com/groups/flippersupport/permalink/911822855965040/).

Reviewed By: nikoant

Differential Revision: D22411617

fbshipit-source-id: ca1078bf418532863823fb3748e9edea4526cbc2

desktop/app/src/App.tsx

@@ -65,7 +65,7 @@ type DispatchProps = {
   setActiveSheet: typeof setActiveSheet;
 };
 
-const MainContent = styled(FlexRow)({
+const MainContent = styled(FlexColumn)({
   height: 'calc(100vh - 38px)',
 });
 
@@ -154,31 +154,33 @@ export class App extends React.Component<Props> {
     return (
       <FlexColumn grow={true}>
         <TitleBar version={version} />
-        <DoctorBar />
-        <ErrorBar />
         <Sheet>{this.getSheet}</Sheet>
         <MainContent>
-          {this.props.leftSidebarVisible && <MainSidebar2 />}
+          <DoctorBar />
-          <PluginContent>
+          <ErrorBar />
-            {this.props.staticView != null ? (
+          <FlexRow grow scrollable>
-              React.createElement(this.props.staticView, {
+            {this.props.leftSidebarVisible && <MainSidebar2 />}
-                logger: this.props.logger,
+            <PluginContent>
-              })
+              {this.props.staticView != null ? (
-            ) : (
+                React.createElement(this.props.staticView, {
-              <PluginContainer logger={this.props.logger} />
+                  logger: this.props.logger,
-            )}
+                })
-            <div
+              ) : (
-              id="flipper-out-of-contents-container"
+                <PluginContainer logger={this.props.logger} />
-              style={{
+              )}
-                display: 'none',
+              <div
-                position: 'absolute',
+                id="flipper-out-of-contents-container"
-                right: 0,
+                style={{
-                bottom: 0,
+                  display: 'none',
-                left: 0,
+                  position: 'absolute',
-                top: 0,
+                  right: 0,
-              }}
+                  bottom: 0,
-            />
+                  left: 0,
-          </PluginContent>
+                  top: 0,
+                }}
+              />
+            </PluginContent>
+          </FlexRow>
         </MainContent>
         <StatusBar />
       </FlexColumn>