Auto merge of #13988 - dsprenkels:tidy-fncalls, r=Wafflespeanut

test-tidy: Check for space between function name and `(`

<!-- Please describe your changes on the following line: -->

Disallow an extraneous space in a function call between
the function name and the opening parenthesis in Rust
code, while ignoring macro declarations.

---

<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy --all` does not report any errors
- [x] `./mach test-tidy --self` does not report any errors
- [x] These changes fix #13980

<!-- Either: -->
- [x] There are tests for these changes, these are written in
 - `python/tidy/servo_tidy_tests/rust_tidy.rs`
 - `python/tidy/servo_tidy_tests/test_tidy.py`
- [ ] These changes do not require tests

<!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. -->

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components/script/dom/htmliframeelement.rs

@@ -416,8 +416,8 @@ pub fn Navigate(iframe: &HTMLIFrameElement, direction: TraversalDirection) -> Er
 
         Ok(())
     } else {
-        debug!("this frame is not mozbrowser: mozbrowser attribute missing, or not a top
-            level window, or mozbrowser preference not set (use --pref dom.mozbrowser.enabled)");
+        debug!(concat!("this frame is not mozbrowser: mozbrowser attribute missing, or not a top",
+            "level window, or mozbrowser preference not set (use --pref dom.mozbrowser.enabled)"));
         Err(Error::NotSupported)
     }
 }
@@ -499,8 +499,8 @@ impl HTMLIFrameElementMethods for HTMLIFrameElement {
             }
             Ok(())
         } else {
-            debug!("this frame is not mozbrowser: mozbrowser attribute missing, or not a top
-                level window, or mozbrowser preference not set (use --pref dom.mozbrowser.enabled)");
+            debug!(concat!("this frame is not mozbrowser: mozbrowser attribute missing, or not a top",
+                "level window, or mozbrowser preference not set (use --pref dom.mozbrowser.enabled)"));
             Err(Error::NotSupported)
         }
     }
@@ -511,8 +511,8 @@ impl HTMLIFrameElementMethods for HTMLIFrameElement {
             self.set_visible(visible);
             Ok(())
         } else {
-            debug!("this frame is not mozbrowser: mozbrowser attribute missing, or not a top
-                level window, or mozbrowser preference not set (use --pref dom.mozbrowser.enabled)");
+            debug!(concat!("this frame is not mozbrowser: mozbrowser attribute missing, or not a top",
+                "level window, or mozbrowser preference not set (use --pref dom.mozbrowser.enabled)"));
             Err(Error::NotSupported)
         }
     }
@@ -522,8 +522,8 @@ impl HTMLIFrameElementMethods for HTMLIFrameElement {
         if self.Mozbrowser() {
             Ok(self.visibility.get())
         } else {
-            debug!("this frame is not mozbrowser: mozbrowser attribute missing, or not a top
-                level window, or mozbrowser preference not set (use --pref dom.mozbrowser.enabled)");
+            debug!(concat!("this frame is not mozbrowser: mozbrowser attribute missing, or not a top",
+                "level window, or mozbrowser preference not set (use --pref dom.mozbrowser.enabled)"));
             Err(Error::NotSupported)
         }
     }

components/script/dom/treewalker.rs

@@ -215,7 +215,7 @@ impl TreeWalkerMethods for TreeWalker {
                 }
                 match node.GetFirstChild() {
                     None => break,
-                    Some (child) => {
+                    Some(child) => {
                         // "1. Set node to its first child."
                         node = child;
                         // "2. Filter node and set result to the return value."

components/script/dom/xmlhttprequest.rs

@@ -525,7 +525,7 @@ impl XMLHttpRequestMethods for XMLHttpRequest {
         // Step 7
         self.upload_complete.set(match extracted {
             None => true,
-            Some (ref e) if e.0.is_empty() => true,
+            Some(ref e) if e.0.is_empty() => true,
             _ => false
         });
         // Step 8