Add contrast setting in dev options

See the attached video from b/266071578#comment2 to see how the setting
looks like.

Bug: 266071578
Test: atest ContrastDialogTest
Test: atest ContrastDialogControllerTest
Change-Id: Id9fc31a0562059814d4e342ea8095adc5b53d5f3
diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index ccf002a..863ae70 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -2785,6 +2785,7 @@
             </intent-filter>
             <intent-filter>
                 <action android:name="com.android.settings.action.SETTINGS" />
+                <action android:name="com.android.intent.action.SHOW_CONTRAST_DIALOG" />
             </intent-filter>
             <meta-data android:name="com.android.settings.order" android:value="-40"/>
             <meta-data android:name="com.android.settings.category"