Revert "Avoid a potential race condition on mDisplays"

This reverts commit 8d6c16dc3dc8b88a0046f53668a4e3be074507ff.

Bug: b/37282502
Change-Id: Ibf64607f9e14ede201510e2c1b502c49a31e9f2a
diff --git a/services/surfaceflinger/DisplayHardware/HWComposer.cpp b/services/surfaceflinger/DisplayHardware/HWComposer.cpp
index 32739b6..09434f6 100644
--- a/services/surfaceflinger/DisplayHardware/HWComposer.cpp
+++ b/services/surfaceflinger/DisplayHardware/HWComposer.cpp
@@ -206,7 +206,7 @@
         }
         disp = DisplayDevice::DISPLAY_EXTERNAL;
     }
-    mEventHandler->onHotplugReceived(this, disp,
+    mEventHandler->onHotplugReceived(disp,
             connected == HWC2::Connection::Connected);
 }