Fix macos pkg installer when rust-docs is not available.

Author: ehuss

src/bootstrap/dist.rs

@@ -1488,7 +1488,7 @@ impl Step for Extended {
 
         let xform = |p: &Path| {
             let mut contents = t!(fs::read_to_string(p));
-            for tool in &["rust-demangler", "miri"] {
+            for tool in &["rust-demangler", "miri", "rust-docs"] {
                 if !built_tools.contains(tool) {
                     contents = filter(&contents, tool);
                 }

src/etc/installer/pkg/Distribution.xml

@@ -15,7 +15,9 @@
       <line choice="rustc"/>
       <line choice="rust-std"/>
       <line choice="cargo"/>
+      <!-- tool-rust-docs-start -->
       <line choice="rust-docs"/>
+      <!-- tool-rust-docs-end -->
       </line>
       <line choice="uninstall" />
     </choices-outline>
@@ -55,15 +57,19 @@
         >
         <pkg-ref id="org.rust-lang.rust-std"/>
     </choice>
+    <!-- tool-rust-docs-start -->
     <choice id="rust-docs" visible="true"
         title="Documentation" description="HTML documentation."
         selected="(!choices.uninstall.selected &amp;&amp; choices['rust-docs'].selected) || (choices.uninstall.selected &amp;&amp; choices.install.selected)"
         >
         <pkg-ref id="org.rust-lang.rust-docs"/>
     </choice>
+    <!-- tool-rust-docs-end -->
     <pkg-ref id="org.rust-lang.rustc" version="0" onConclusion="none">rustc.pkg</pkg-ref>
     <pkg-ref id="org.rust-lang.cargo" version="0" onConclusion="none">cargo.pkg</pkg-ref>
+    <!-- tool-rust-docs-start -->
     <pkg-ref id="org.rust-lang.rust-docs" version="0" onConclusion="none">rust-docs.pkg</pkg-ref>
+    <!-- tool-rust-docs-end -->
     <pkg-ref id="org.rust-lang.rust-std" version="0" onConclusion="none">rust-std.pkg</pkg-ref>
     <pkg-ref id="org.rust-lang.uninstall" version="0" onConclusion="none">uninstall.pkg</pkg-ref>
     <background file="rust-logo.png" mime-type="image/png"