Enable 'enable-floating-virtual-keyboard' by default.

Bug: 771466, 776260
Test: Confirm that floating VK is enabled after setting the flag to 'Default'.
Change-Id: I2e4a26ee05dbaba16cd78f0768e6fae3d079bcc4
Reviewed-on: https://chromium-review.googlesource.com/954804Reviewed-by: Sadrul Chowdhury <sadrul@chromium.org>
Commit-Queue: Yuichiro Hanada <yhanada@chromium.org>
Cr-Commit-Position: refs/heads/master@{#541976}

ui/base/ui_base_features.cc

@@ -14,7 +14,7 @@ namespace features {
 
 // Enables the floating virtual keyboard behavior.
 const base::Feature kEnableFloatingVirtualKeyboard = {
-    "enable-floating-virtual-keyboard", base::FEATURE_DISABLED_BY_DEFAULT};
+    "enable-floating-virtual-keyboard", base::FEATURE_ENABLED_BY_DEFAULT};
 
 // Applies the material design mode to elements throughout Chrome (not just top
 // Chrome).