[tint][fuzz] Add basic base-64 comments to dictionary.txt

This may help the fuzzers add comments that can be processed as out-of-band data for fuzzers with additional parameters.

Bug: tint:2223
Change-Id: I64ec1fdf842723163368275a044f644b9b4b7ee9
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/185630
Reviewed-by: James Price <jrprice@google.com>
Commit-Queue: Ben Clayton <bclayton@google.com>
Reviewed-by: Ryan Harrison <rharrison@chromium.org>
diff --git a/src/tint/cmd/fuzz/wgsl/dictionary.txt b/src/tint/cmd/fuzz/wgsl/dictionary.txt
index cc0d9d3..a8a1694 100644
--- a/src/tint/cmd/fuzz/wgsl/dictionary.txt
+++ b/src/tint/cmd/fuzz/wgsl/dictionary.txt
@@ -55,6 +55,9 @@
 "->"
 "."
 "/"
+"// AAAA"
+"// AAAB"
+"// BAAA"
 "/="
 ":"
 ";"
diff --git a/src/tint/cmd/fuzz/wgsl/dictionary.txt.tmpl b/src/tint/cmd/fuzz/wgsl/dictionary.txt.tmpl
index 5ffad37..e5605d7 100644
--- a/src/tint/cmd/fuzz/wgsl/dictionary.txt.tmpl
+++ b/src/tint/cmd/fuzz/wgsl/dictionary.txt.tmpl
@@ -17,7 +17,7 @@
 
 {{- $tokens := List}}
 
-{{- /* ============================== Operators ============================== */ -}}
+{{- /* ========================= Operators & Keywords ======================== */ -}}
 {{- $tokens = Append $tokens
     "!"
     "!="
@@ -105,6 +105,13 @@
     "true" "false"
 -}}
 
+{{- /* =========================== Base64 comments =========================== */ -}}
+{{- $tokens = Append $tokens
+    "// AAAA"
+    "// BAAA"
+    "// AAAB"
+-}}
+
 {{- /* ========================== Builtin functions ========================== */ -}}
 {{- range $W.Sem.Builtins}}{{$tokens = Append $tokens .Name}}{{end -}}