Enable the LocalScreenCasting feature by default

This feature is getting rolled out on M66. Enable it by default for M67.

Bug: 758005
Change-Id: Id96a86f8e7140f61496b8bfcf7ac5c4f3e00b56a
Reviewed-on: https://chromium-review.googlesource.com/1003519Reviewed-by: Derek Cheng <imcheng@chromium.org>
Commit-Queue: Takumi Fujimoto <takumif@chromium.org>
Cr-Commit-Position: refs/heads/master@{#550174}

chrome/common/chrome_features.cc

@@ -331,7 +331,7 @@ const base::Feature kIncompatibleApplicationsWarning{
 #if !defined(OS_ANDROID)
 // Enables Casting a Presentation API-enabled website to a secondary display.
 const base::Feature kLocalScreenCasting{"LocalScreenCasting",
-                                        base::FEATURE_DISABLED_BY_DEFAULT};
+                                        base::FEATURE_ENABLED_BY_DEFAULT};
 #endif
 
 // Enables or disables the Location Settings Dialog (LSD). The LSD is an Android