Advertise QtCreator v20+ built-in GN support

Change-Id: I60fd837d418c079e8dc8df13ce8049eb4d9ec6ab
Reviewed-on: https://gn-review.googlesource.com/c/gn/+/21900
Reviewed-by: Takuto Ikuta <tikuta@google.com>
Reviewed-by: David Turner <digit@google.com>
Commit-Queue: David Turner <digit@google.com>

docs/reference.md

diff --git a/docs/reference.md b/docs/reference.md
index 27d5af0..b2dc306 100644
--- a/docs/reference.md
+++ b/docs/reference.md
@@ -781,6 +781,19 @@
       provided by the --ninja-executable switch. Also see "gn help clean_stale".
 ```
 
+#### **IDE support**
+
+```
+  QtCreator (version 20 and newer) has built-in support for GN-based projects.
+  A GN project can be opened directly by selecting the top-level .gn or BUILD.gn file.
+
+  QtCreator's GN support plugin provides:
+    - Project tree with all targets, sources & data files
+    - Accurate code model based on defines and compile flags
+    - Code navigation and completion
+    - Ability to run and debug targets directly
+```
+
 #### **IDE options**
 
 ```

src/gn/command_gen.cc

diff --git a/src/gn/command_gen.cc b/src/gn/command_gen.cc
index 648f36e..de8b89f 100644
--- a/src/gn/command_gen.cc
+++ b/src/gn/command_gen.cc
@@ -551,6 +551,17 @@
       option requires a ninja executable of at least version 1.10.0. It can be
       provided by the --ninja-executable switch. Also see "gn help clean_stale".
 
+IDE support
+
+  QtCreator (version 20 and newer) has built-in support for GN-based projects.
+  A GN project can be opened directly by selecting the top-level .gn or BUILD.gn file.
+
+  QtCreator's GN support plugin provides:
+    - Project tree with all targets, sources & data files
+    - Accurate code model based on defines and compile flags
+    - Code navigation and completion
+    - Ability to run and debug targets directly
+
 IDE options
 
   GN optionally generates files for IDE. Files won't be overwritten if their