Misc changes (#14702)

This mainly fixes `with_leading_whitespace` not always adding the
whitespace it can.

changelog: None

tests/ui-toml/collapsible_if/collapsible_if.fixed

@@ -13,7 +13,7 @@ fn main() {
     //~^^^^^^ collapsible_if
 
     // The following tests check for the fix of https://github.com/rust-lang/rust-clippy/issues/798
-    if x == "hello"  // Inner comment
+    if x == "hello" // Inner comment
         && y == "world" {
             println!("Hello world!");
         }
@@ -26,7 +26,7 @@ fn main() {
         }
     //~^^^^^^ collapsible_if
 
-    if x == "hello"  /* Inner comment */
+    if x == "hello" /* Inner comment */
         && y == "world" {
             println!("Hello world!");
         }

tests/ui-toml/collapsible_if/collapsible_if.stderr

@@ -32,7 +32,7 @@ LL | |     }
    |
 help: collapse nested if block
    |
-LL ~     if x == "hello"  // Inner comment
+LL ~     if x == "hello" // Inner comment
 LL ~         && y == "world" {
 LL |             println!("Hello world!");
 LL ~         }
@@ -70,7 +70,7 @@ LL | |     }
    |
 help: collapse nested if block
    |
-LL ~     if x == "hello"  /* Inner comment */
+LL ~     if x == "hello" /* Inner comment */
 LL ~         && y == "world" {
 LL |             println!("Hello world!");
 LL ~         }

tests/ui/manual_inspect.fixed

@@ -107,7 +107,7 @@ fn main() {
             let _ = || {
                 let _x = x;
             };
-            return ;
+            return;
         }
         println!("test");
     });

tests/ui/manual_inspect.stderr

@@ -98,7 +98,7 @@ LL |         if x.is_empty() {
 LL |             let _ = || {
 LL ~                 let _x = x;
 LL |             };
-LL ~             return ;
+LL ~             return;
 LL |         }
 LL ~         println!("test");
    |