Flip Continue Reading flag

This patch flips the flag of Continue Reading to default on.

Bug: 882602, 843839
Test: manual.
Change-Id: Idaebea1a12926d1a64482b06af3644e55fc01b4a
Reviewed-on: https://chromium-review.googlesource.com/1217593Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Commit-Queue: Tao Wu <wutao@chromium.org>
Cr-Commit-Position: refs/heads/master@{#590082}

ash/public/cpp/app_list/app_list_features.cc

@@ -30,7 +30,7 @@ const base::Feature kEnableAppsGridGapFeature{"EnableAppsGridGapFeature",
 const base::Feature kEnableNewStyleLauncher{"EnableNewStyleLauncher",
                                             base::FEATURE_ENABLED_BY_DEFAULT};
 const base::Feature kEnableContinueReading{"EnableContinueReading",
-                                           base::FEATURE_DISABLED_BY_DEFAULT};
+                                           base::FEATURE_ENABLED_BY_DEFAULT};
 const base::Feature kEnableZeroStateSuggestions{
     "EnableZeroStateSuggestions", base::FEATURE_DISABLED_BY_DEFAULT};
 const base::Feature kEnableAppListSearchAutocomplete{