SF: Use consistent names for display references

This CL renames IBinder tokens to "displayToken", and DisplayDevice
references to "display". It also cleans up style for affected lines.

Bug: 74619554
Test: Build
Change-Id: I04fc7264bf2a856caf30d662029b6f603f432938
diff --git a/services/surfaceflinger/DisplayDevice.h b/services/surfaceflinger/DisplayDevice.h
index 6d1fb16..79ba15d 100644
--- a/services/surfaceflinger/DisplayDevice.h
+++ b/services/surfaceflinger/DisplayDevice.h
@@ -194,7 +194,7 @@
      */
     int getPowerMode() const;
     void setPowerMode(int mode);
-    bool isDisplayOn() const;
+    bool isPoweredOn() const;
 
     ui::ColorMode getActiveColorMode() const;
     void setActiveColorMode(ui::ColorMode mode);