Change FragmentItem and EditingNG ENABLE_BY_DEFAULT

These are changed to `status: "stable"` in
`runtime_enabled_features.json5`, but `base:Feature`s were not
updated. This patch changes them to `FEATURE_ENABLED_BY_DEFAULT`.

Bug: 707656, 982194
Change-Id: I026a6b7f4b13390ce9fe4f5d2afe4d0c820d4580
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2560075Reviewed-by: Kent Tamura <tkent@chromium.org>
Reviewed-by: Yoshifumi Inoue <yosin@chromium.org>
Commit-Queue: Koji Ishii <kojii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#830951}

third_party/blink/common/features.cc

@@ -75,7 +75,7 @@ const base::Feature kTopLevelAwait{"TopLevelAwait",
                                    base::FEATURE_DISABLED_BY_DEFAULT};
 
 // Enable EditingNG by default. This feature is for a kill switch.
-const base::Feature kEditingNG{"EditingNG", base::FEATURE_DISABLED_BY_DEFAULT};
+const base::Feature kEditingNG{"EditingNG", base::FEATURE_ENABLED_BY_DEFAULT};
 
 // Enable LayoutNG.
 const base::Feature kLayoutNG{"LayoutNG", base::FEATURE_ENABLED_BY_DEFAULT};
@@ -88,7 +88,7 @@ const base::Feature kLayoutNGTextControl{"LayoutNGTextControl",
                                          base::FEATURE_DISABLED_BY_DEFAULT};
 
 const base::Feature kFragmentItem{"FragmentItem",
-                                  base::FEATURE_DISABLED_BY_DEFAULT};
+                                  base::FEATURE_ENABLED_BY_DEFAULT};
 
 const base::Feature kMixedContentAutoupgrade{"AutoupgradeMixedContent",
                                              base::FEATURE_ENABLED_BY_DEFAULT};