[Android Webview] Flag for Image Drag

Add a feature flag for webview Image drag/drop.


Bug: 1353048
Change-Id: Id0176a297ce55cea7fbc3c02539f7246c4f94f3c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4061245
Commit-Queue: Peter Conn <peconn@chromium.org>
Reviewed-by: Nate Fischer <ntfschr@chromium.org>
Reviewed-by: Peter Conn <peconn@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1080286}

android_webview/browser/aw_content_browser_client.cc

@@ -528,6 +528,8 @@ void AwContentBrowserClient::OverrideWebkitPrefs(
   if (aw_settings) {
     aw_settings->PopulateWebPreferences(web_prefs);
   }
+  web_prefs->modal_context_menu =
+      !base::FeatureList::IsEnabled(features::kWebViewImageDrag);
 }
 
 std::vector<std::unique_ptr<content::NavigationThrottle>>

android_webview/common/aw_features.cc

@@ -141,5 +141,10 @@ BASE_FEATURE(kWebViewClientHintsControllerDelegate,
              "WebViewClientHintsControllerDelegate",
              base::FEATURE_DISABLED_BY_DEFAULT);
 
+// This enables image drage out for Webview.
+BASE_FEATURE(kWebViewImageDrag,
+             "WebViewImageDrag",
+             base::FEATURE_ENABLED_BY_DEFAULT);
+
 }  // namespace features
 }  // namespace android_webview

android_webview/common/aw_features.h

@@ -26,6 +26,7 @@ BASE_DECLARE_FEATURE(kWebViewEnumerateDevicesCache);
 BASE_DECLARE_FEATURE(kWebViewExtraHeadersSameOriginOnly);
 BASE_DECLARE_FEATURE(kWebViewForceDarkModeMatchTheme);
 BASE_DECLARE_FEATURE(kWebViewHitTestInBlinkOnTouchStart);
+BASE_DECLARE_FEATURE(kWebViewImageDrag);
 BASE_DECLARE_FEATURE(kWebViewJavaJsBridgeMojo);
 BASE_DECLARE_FEATURE(kWebViewMeasureScreenCoverage);
 BASE_DECLARE_FEATURE(kWebViewMixedContentAutoupgrades);

android_webview/java/src/org/chromium/android_webview/common/ProductionSupportedFlagList.java

@@ -351,6 +351,8 @@ public final class ProductionSupportedFlagList {
             Flag.baseFeature(ContentFeatures.PERSISTENT_ORIGIN_TRIALS,
                     "If enabled, servers will be able to use persistent origin trials "
                             + "on this device."),
+            Flag.baseFeature(AwFeatures.WEBVIEW_IMAGE_DRAG,
+                    "If enabled, images can be dragged out from Webview"),
             // Add new commandline switches and features above. The final entry should have a
             // trailing comma for cleaner diffs.
     };