Fix newShaderBlock return;

api/init.lua

@@ -8628,6 +8628,7 @@ return {
               },
               returns = {
                 {
+                  name = "shaderBlock",
                   type = "ShaderBlock",
                   description = "The new ShaderBlock."
                 }

api/lovr/graphics/newShaderBlock.lua

@@ -37,6 +37,7 @@ return {
   },
   returns = {
     {
+      name = 'shaderBlock',
       type = 'ShaderBlock',
       description = 'The new ShaderBlock.'
     }

api/main.lua

@@ -265,6 +265,16 @@ local function validateFunction(fn)
     warnIf(not found, 'Unknown tag %s for %s', fn.tag, fn.key)
   end
 
+  for _, variant in ipairs(fn.variants) do
+    for _, arg in ipairs(variant.arguments) do
+      warnIf(not arg.name, 'Nameless argument for variant of %s', fn.key)
+    end
+
+    for _, ret in ipairs(variant.returns) do
+      warnIf(not ret.name, 'Nameless return for variant of %s', fn.key)
+    end
+  end
+
   validateRelated(fn)
 end