CompletionSuggestion API for arg list text ranges.

pkg/analysis_server/tool/spec/spec_input.html

Index: pkg/analysis_server/tool/spec/spec_input.html
diff --git a/pkg/analysis_server/tool/spec/spec_input.html b/pkg/analysis_server/tool/spec/spec_input.html
index 24bbf4898e33883fcf25a9aa09f657ae0ad40bd8..e2a4c158ba843ebfcb417a9cc103687a464a1aa8 100644
--- a/pkg/analysis_server/tool/spec/spec_input.html
+++ b/pkg/analysis_server/tool/spec/spec_input.html
@@ -2439,6 +2439,18 @@
               source contents on the client side.
             </p>
           </field>
+          <field name="defaultArgumentListTextRanges" optional="true">
+            <list><ref>int</ref></list>
+            <p>
+              Pairs of offsets and lengths describing 'defaultArgumentListString'
+              text ranges suitable for use by clients to set up linked edits of
+              default argument source contents. For example, given an argument
+              list string 'x, y', the corresponding text range [0, 1, 3, 1],
+              indicates two text ranges of length 1, starting at offsets 0 and 3.
+              Clients can use these ranges to treat the 'x' and 'y' values
+              specially for linked edits.
+            </p>
+          </field>
           <field name="element" optional="true">
             <ref>Element</ref>
             <p>