Cherry-pick 272448.473@safari-7618-branch (00b3f3c). https://bugs.web…

…kit.org/show_bug.cgi?id=268731

    Block "setMediaOverridesForTesting" media IPC endpoints when not testing and instead reset values
    https://bugs.webkit.org/show_bug.cgi?id=268731
    rdar://122218365

    Reviewed by Youenn Fablet.

    The fix in https://commits.webkit.org/272448.445@safari-7618-branch was insufficient as
    the setMediaOverridesForTesting IPC endpoints is also used to reset the flags to their default.

    So rather than disabling the IPC endpoints altogether we restrict its use to only reset
    the default values (which are all unset).

    * Source/WebKit/GPUProcess/GPUConnectionToWebProcess.cpp:
    (WebKit::GPUConnectionToWebProcess::setMediaOverridesForTesting):
    * Source/WebKit/GPUProcess/GPUConnectionToWebProcess.messages.in:

    Canonical link: https://commits.webkit.org/272448.473@safari-7618-branch

Canonical link: https://commits.webkit.org/266719.376@webkitglib/2.42

Source/WebKit/GPUProcess/GPUConnectionToWebProcess.cpp

@@ -813,6 +813,16 @@ void GPUConnectionToWebProcess::releaseRemoteCommandListener(RemoteRemoteCommand
 
 void GPUConnectionToWebProcess::setMediaOverridesForTesting(MediaOverridesForTesting overrides)
 {
+    if (!allowTestOnlyIPC()) {
+        MESSAGE_CHECK(!overrides.systemHasAC && !overrides.systemHasBattery && !overrides.vp9HardwareDecoderDisabled && !overrides.vp9DecoderDisabled && !overrides.vp9ScreenSizeAndScale);
+#if PLATFORM(COCOA)
+#if ENABLE(VP9)
+        VP9TestingOverrides::singleton().resetOverridesToDefaultValues();
+#endif
+        SystemBatteryStatusTestingOverrides::singleton().resetOverridesToDefaultValues();
+#endif
+        return;
+    }
 #if ENABLE(VP9) && PLATFORM(COCOA)
     VP9TestingOverrides::singleton().setHardwareDecoderDisabled(WTFMove(overrides.vp9HardwareDecoderDisabled));
     VP9TestingOverrides::singleton().setVP9DecoderDisabled(WTFMove(overrides.vp9DecoderDisabled));