Add an experimental flag for ephemeral flash permissions.

Flash permissions are on the way to become only persistent through
current session.
This CL adds an experimental flag for the required changes.

Bug: 850062
Change-Id: Iccc22dbb2c9d63711e8b58c76e59a6939bd58d46
Reviewed-on: https://chromium-review.googlesource.com/1105986Reviewed-by: Martin Šrámek <msramek@chromium.org>
Commit-Queue: Ramin Halavati <rhalavati@chromium.org>
Cr-Commit-Position: refs/heads/master@{#568776}

chrome/browser/about_flags.cc

@@ -3958,6 +3958,11 @@ const FeatureEntry kFeatureEntries[] = {
      flag_descriptions::kEnableCSSFragmentIdentifiersDescription, kOsAll,
      FEATURE_VALUE_TYPE(features::kCSSFragmentIdentifiers)},
 
+    {"enable-ephemeral-flash-permission",
+     flag_descriptions::kEnableEphemeralFlashPermissionName,
+     flag_descriptions::kEnableEphemeralFlashPermissionDescription, kOsDesktop,
+     SINGLE_VALUE_TYPE(switches::kEnableEphemeralFlashPermission)},
+
     // NOTE: Adding a new flag requires adding a corresponding entry to enum
     // "LoginCustomFlags" in tools/metrics/histograms/enums.xml. See "Flag
     // Histograms" in tools/metrics/histograms/README.md (run the

chrome/browser/flag_descriptions.cc

@@ -410,6 +410,12 @@ const char kEnableCursorMotionBlurName[] = "Enable Cursor Motion Blur";
 const char kEnableCursorMotionBlurDescription[] =
     "Enable motion blur effect for the cursor.";
 
+const char kEnableEphemeralFlashPermissionName[] =
+    "Enable Ephemeral Flash Permissions";
+const char kEnableEphemeralFlashPermissionDescription[] =
+    "When enabled, Flash plugin permissions are reset at the end of the "
+    "browser session.";
+
 const char kEnableNoScriptPreviewsName[] = "NoScript previews";
 
 const char kEnableNoScriptPreviewsDescription[] =

chrome/browser/flag_descriptions.h

@@ -281,6 +281,9 @@ extern const char kEnableCSSFragmentIdentifiersDescription[];
 extern const char kEnableCursorMotionBlurName[];
 extern const char kEnableCursorMotionBlurDescription[];
 
+extern const char kEnableEphemeralFlashPermissionName[];
+extern const char kEnableEphemeralFlashPermissionDescription[];
+
 extern const char kEnableNoScriptPreviewsName[];
 extern const char kEnableNoScriptPreviewsDescription[];
 

chrome/common/chrome_features.cc

@@ -224,6 +224,10 @@ const base::Feature kDownloadsLocationChange{"DownloadsLocationChange",
                                              base::FEATURE_DISABLED_BY_DEFAULT};
 #endif
 
+// Makes Flash plugin permissions persistent only through the current session.
+const base::Feature kEnableEphemeralFlashPermission{
+    "EnableEphemeralFlashPermission", base::FEATURE_DISABLED_BY_DEFAULT};
+
 // An experimental way of showing app banners, which has modal banners and gives
 // developers more control over when to show them.
 const base::Feature kExperimentalAppBanners {

chrome/common/chrome_features.h

@@ -118,6 +118,8 @@ extern const base::Feature kDownloadsForeground;
 extern const base::Feature kDownloadsLocationChange;
 #endif
 
+extern const base::Feature kEnableEphemeralFlashPermission;
+
 extern const base::Feature kExperimentalAppBanners;
 
 #if defined(OS_CHROMEOS)

chrome/common/chrome_switches.cc

@@ -292,6 +292,10 @@ const char kEnableDevToolsExperiments[]     = "enable-devtools-experiments";
 // Enables Domain Reliability Monitoring.
 const char kEnableDomainReliability[] = "enable-domain-reliability";
 
+// Makes Flash plugin permissions persistent only through the current session.
+const char kEnableEphemeralFlashPermission[] =
+    "enable-ephemeral-flash-permission";
+
 // Enables logging for extension activity.
 const char kEnableExtensionActivityLogging[] =
     "enable-extension-activity-logging";

chrome/common/chrome_switches.h

@@ -96,6 +96,7 @@ extern const char kEnableCloudPrintProxy[];
 extern const char kEnableDeviceDiscoveryNotifications[];
 extern const char kEnableDevToolsExperiments[];
 extern const char kEnableDomainReliability[];
+extern const char kEnableEphemeralFlashPermission[];
 extern const char kEnableExtensionActivityLogging[];
 extern const char kEnableExtensionActivityLogTesting[];
 extern const char kEnableFastUnload[];

tools/metrics/histograms/enums.xml

@@ -27538,6 +27538,7 @@ from previous Chrome versions.
   <int value="-699767107" label="enable-sync-app-list"/>
   <int value="-699198009" label="KeyboardShortcutViewer:enabled"/>
   <int value="-697751423" label="disable-quickoffice-component-app"/>
+  <int value="-694372915" label="enable-ephemeral-flash-permission"/>
   <int value="-684900739" label="disable-merge-key-char-events"/>
   <int value="-684223908" label="enable-android-wallpapers-app"/>
   <int value="-680787130" label="ExperimentalVRFeatures:disabled"/>