Auto merge of #21921 - servo:jdm-patch-6-1, r=gw3583

Use a depth buffer when embedding Servo on android.

Webrender uses the z-buffer but does not check that it's present. We need to provide one for pages to render correctly.

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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #21807
- [x] These changes do not require tests because there are no automated tests for embedding Servo in Firefox Reality.

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support/android/apk/servoview/src/main/java/org/mozilla/servoview/ServoSurface.java

@@ -136,7 +136,7 @@ public class ServoSurface {
                     EGL14.EGL_GREEN_SIZE, 8,
                     EGL14.EGL_BLUE_SIZE, 8,
                     EGL14.EGL_ALPHA_SIZE, 8,
-                    EGL14.EGL_DEPTH_SIZE, 0,
+                    EGL14.EGL_DEPTH_SIZE, 24,
                     EGL14.EGL_STENCIL_SIZE, 0,
                     EGL14.EGL_NONE
             };