Desktop PWAs: Enable minimal-ui

minimal-ui desktop PWAs behave similarly to standalone PWAs,
but with Back and Reload buttons at the left end of the title bar.

https://www.w3.org/TR/appmanifest/#dom-displaymodetype-minimal-ui

Bug: 1007151
Change-Id: I86920c20a5af89aefdabfdaba89996ab267e0f19
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1914588
Commit-Queue: Alan Cutter <alancutter@chromium.org>
Auto-Submit: Eric Willigers <ericwilligers@chromium.org>
Reviewed-by: Alan Cutter <alancutter@chromium.org>
Cr-Commit-Position: refs/heads/master@{#715174}

chrome/common/chrome_features.cc

@@ -250,7 +250,7 @@ const base::Feature kDesktopCaptureTabSharingInfobar{
 
 // Enables or disables new Desktop PWA support for minimal-ui display mode.
 const base::Feature kDesktopMinimalUI{"DesktopMinimalUI",
-                                      base::FEATURE_DISABLED_BY_DEFAULT};
+                                      base::FEATURE_ENABLED_BY_DEFAULT};
 
 // Enables or disables new Desktop PWAs implementation that does not use
 // extensions.