DevTools: Introduce Landing page for Timeline panel.

third_party/WebKit/Source/devtools/front_end/main/Main.js

Index: third_party/WebKit/Source/devtools/front_end/main/Main.js
diff --git a/third_party/WebKit/Source/devtools/front_end/main/Main.js b/third_party/WebKit/Source/devtools/front_end/main/Main.js
index 52c64817f9a209ee4175bee99364f07b786c9b75..b15af98ede739cae7fc1e35851202ee8b9fde487 100644
--- a/third_party/WebKit/Source/devtools/front_end/main/Main.js
+++ b/third_party/WebKit/Source/devtools/front_end/main/Main.js
@@ -111,6 +111,7 @@ Main.Main = class {
     Runtime.experiments.register('sourceDiff', 'Source diff');
     Runtime.experiments.register('terminalInDrawer', 'Terminal in drawer', true);
     Runtime.experiments.register('timelineInvalidationTracking', 'Timeline invalidation tracking', true);
+    Runtime.experiments.register('timelineLandingPage', 'Timeline landing page', true);
     Runtime.experiments.register('timelineRecordingPerspectives', 'Timeline recording perspectives UI');
     Runtime.experiments.register('timelineTracingJSProfile', 'Timeline tracing based JS profiler', true);
     Runtime.experiments.register('timelineV8RuntimeCallStats', 'V8 Runtime Call Stats on Timeline', true);