Add a flush before looping to get the sync status.

src/tests/gl_tests/FenceSyncTests.cpp

@@ -230,13 +230,6 @@ TEST_P(FenceSyncTest, BasicQueries)
 // Test that basic usage works and doesn't generate errors or crash
 TEST_P(FenceSyncTest, BasicOperations)
 {
-    // TODO(geofflang): Figure out why this is broken on Intel OpenGL
-    if (isIntel() && getPlatformRenderer() == EGL_PLATFORM_ANGLE_TYPE_OPENGL_ANGLE)
-    {
-        std::cout << "Test skipped on Intel OpenGL." << std::endl;
-        return;
-    }
-
     glClearColor(1.0f, 0.0f, 1.0f, 1.0f);
 
     GLsync sync = glFenceSync(GL_SYNC_GPU_COMMANDS_COMPLETE, 0);
@@ -245,6 +238,10 @@ TEST_P(FenceSyncTest, BasicOperations)
     glWaitSync(sync, 0, GL_TIMEOUT_IGNORED);
     EXPECT_GL_NO_ERROR();
 
+    // Some drivers don't automatically flush and can enter into an infinite loop
+    // while waiting for the fence to complete.
+    glFlush();
+
     GLsizei length = 0;
     GLint value = 0;
     while (value != GL_SIGNALED)