Inject agents for GL tests.

Otherwise, aemu-gfxstream tests will crash.

Bug: 224794781
Test: presubmit
Change-Id: Ib80a1ca1ac46b4ccfbf1949d42c02e1068fe8889
diff --git a/stream-servers/tests/OpenGLTestContext.h b/stream-servers/tests/OpenGLTestContext.h
index 1d7697e..756307a 100644
--- a/stream-servers/tests/OpenGLTestContext.h
+++ b/stream-servers/tests/OpenGLTestContext.h
@@ -43,6 +43,7 @@
 
 class GLTest : public ::testing::Test {
 protected:
+    static void SetUpTestSuite();
     virtual void SetUp();
     virtual void TearDown();