Move the new gpu mode opt-in behind a stubbed guard

Bug: b/517195732

Author: jmacnak

base/cvd/cuttlefish/host/commands/assemble_cvd/graphics_flags.cc

@@ -431,6 +431,10 @@ GetNeededVhostUserGpuHostRendererFeatures(
 }
 
 #ifndef __APPLE__
+
+// TODO(b/503397840): remove after default updated.
+bool EnableHostRenderingByDefault() { return false; }
+
 std::vector<GpuMode> GetGpuModeCandidates(const GuestConfig& guest_config) {
   if (!guest_config.gpu_mode_candidates.empty()) {
     VLOG(0) << "GPU mode candidates provided by guest.";
@@ -445,13 +449,22 @@ std::vector<GpuMode> GetGpuModeCandidates(const GuestConfig& guest_config) {
     gpu_mode_candidates.push_back(GpuMode::DrmVirgl);
   }
 
-  gpu_mode_candidates.push_back(GpuMode::Gfxstream);
-  gpu_mode_candidates.push_back(GpuMode::GfxstreamGuestAngle);
-  gpu_mode_candidates.push_back(GpuMode::GfxstreamGuestAngleHostSwiftshader);
-  gpu_mode_candidates.push_back(GpuMode::GfxstreamGuestAngleHostLavapipe);
-  gpu_mode_candidates.push_back(GpuMode::GuestSwiftshader);
+  if (EnableHostRenderingByDefault()) {
+    gpu_mode_candidates.push_back(GpuMode::GfxstreamGuestAngle);
+    gpu_mode_candidates.push_back(GpuMode::Gfxstream);
+    gpu_mode_candidates.push_back(GpuMode::GfxstreamGuestAngleHostSwiftshader);
+    gpu_mode_candidates.push_back(GpuMode::GfxstreamGuestAngleHostLavapipe);
+    gpu_mode_candidates.push_back(GpuMode::GuestSwiftshader);
+  } else {
+    gpu_mode_candidates.push_back(GpuMode::GuestSwiftshader);
+    gpu_mode_candidates.push_back(GpuMode::Gfxstream);
+    gpu_mode_candidates.push_back(GpuMode::GfxstreamGuestAngle);
+    gpu_mode_candidates.push_back(GpuMode::GfxstreamGuestAngleHostSwiftshader);
+    gpu_mode_candidates.push_back(GpuMode::GfxstreamGuestAngleHostLavapipe);
+  }
 
   gpu_mode_candidates.push_back(GpuMode::None);
+
   return gpu_mode_candidates;
 }
 

e2etests/cvd/graphics_detector_tests/main_test.go

@@ -44,15 +44,15 @@ func TestLaunchingWithAutoEnablesGfxstream(t *testing.T) {
 	if err != nil {
 		t.Fatalf("failed to get EGL sysprop: %w", err)
 	}
-	if gl_driver != "emulation" {
-		t.Errorf(`"ro.hardware.egl" was "%s"; expected "emulation"`, gl_driver)
+	if gl_driver != "angle" {
+		t.Errorf(`"ro.hardware.egl" was "%s"; expected "angle"`, gl_driver)
 	}
 
 	vk_driver, err := c.GetSyspropString("ro.hardware.vulkan")
 	if err != nil {
 		t.Fatalf("failed to get Vulkan sysprop: %w", err)
 	}
-	if vk_driver != "ranchu" {
-		t.Errorf(`"ro.hardware.vulkan" was "%s"; expected "ranchu"`, vk_driver)
+	if vk_driver != "pastel" {
+		t.Errorf(`"ro.hardware.vulkan" was "%s"; expected "pastel"`, vk_driver)
 	}
 }