Fix compatibility warning for multiview (#8075)

Verify the compatibility between a compiled material and the engine's
setting only when the engine is set up for stereo.

Default materials are always compiled with either 'instanced' or
'multiview. Therefore Filament will emit warnings unintentionally if the
engine is set up for stereo. This commit fixes it.

filament/src/details/Material.cpp

@@ -192,19 +192,27 @@ Material* Material::Builder::build(Engine& engine) {
         return nullptr;
     }
 
+    // Print a warning if the material's stereo type doesn't align with the engine's setting.
     MaterialDomain materialDomain;
+    UserVariantFilterMask variantFilterMask;
     materialParser->getMaterialDomain(&materialDomain);
-    if (materialDomain == MaterialDomain::SURFACE) {
+    materialParser->getMaterialVariantFilterMask(&variantFilterMask);
+    bool const hasStereoVariants = !(variantFilterMask & UserVariantFilterMask(UserVariantFilterBit::STE));
+    if (materialDomain == MaterialDomain::SURFACE && hasStereoVariants) {
         StereoscopicType const engineStereoscopicType = engine.getConfig().stereoscopicType;
-        StereoscopicType materialStereoscopicType = StereoscopicType::NONE;
-        materialParser->getStereoscopicType(&materialStereoscopicType);
-        if (materialStereoscopicType != engineStereoscopicType) {
-            CString name;
-            materialParser->getName(&name);
-            slog.w << "The stereoscopic type in the compiled material '" << name.c_str_safe()
-                    << "' is " << (int)materialStereoscopicType
-                    << ", which is not compatiable with the engine's setting "
-                    << (int)engineStereoscopicType << "." << io::endl;
+        // Default materials are always compiled with either 'instanced' or 'multiview'.
+        // So, we only verify compatibility if the engine is set up for stereo.
+        if (engineStereoscopicType != StereoscopicType::NONE) {
+            StereoscopicType materialStereoscopicType = StereoscopicType::NONE;
+            materialParser->getStereoscopicType(&materialStereoscopicType);
+            if (materialStereoscopicType != engineStereoscopicType) {
+                CString name;
+                materialParser->getName(&name);
+                slog.w << "The stereoscopic type in the compiled material '" << name.c_str_safe()
+                        << "' is " << (int)materialStereoscopicType
+                        << ", which is not compatiable with the engine's setting "
+                        << (int)engineStereoscopicType << "." << io::endl;
+            }
         }
     }