Use SysuiTestCase#runShellCommand.

This (a) makes the test run rather than fail for trying to get the
global instrumentation.
(b) May deflake the test (once it is passing) by waiting for shell
commands to complete before moving on.

Bug: 176891566
Bug: 249756667
Test: com.android.systemui.globalactions.GlobalActionsImeTest
Change-Id: I7dbf1b5443a501bb71dafc7bbd89b43b2a09a0b2

packages/SystemUI/tests/src/com/android/systemui/globalactions/GlobalActionsImeTest.java

@@ -49,6 +49,7 @@ import org.junit.Before;
 import org.junit.Rule;
 import org.junit.Test;
 
+import java.io.IOException;
 import java.util.concurrent.TimeUnit;
 import java.util.function.BooleanSupplier;
 
@@ -148,8 +149,12 @@ public class GlobalActionsImeTest extends SysuiTestCase {
         return false;
     }
 
-    private static void executeShellCommand(String cmd) {
-        InstrumentationRegistry.getInstrumentation().getUiAutomation().executeShellCommand(cmd);
+    private void executeShellCommand(String cmd) {
+        try {
+            runShellCommand(cmd);
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
     }
 
     /**