Revert "Update Robolectric SDK to 30"

This reverts commit 5ed0907cd34faab89b9ba2c55961c072e4f6e2ec.

Reason for revert: b/180139562

Change-Id: I9520993ee925935ab621239686377a39e2e25590
diff --git a/robolectric_tests/config/robolectric.properties b/robolectric_tests/config/robolectric.properties
index 0ac997f..4e811f3 100644
--- a/robolectric_tests/config/robolectric.properties
+++ b/robolectric_tests/config/robolectric.properties
@@ -1,4 +1,4 @@
-sdk=30
+sdk=29
 shadows= \
     com.android.launcher3.shadows.LShadowAppPredictionManager \
     com.android.launcher3.shadows.LShadowAppWidgetManager \