gopls/internal/settings: drop experimental hoverKind=Structured

We thought it was used by govim, but apparently not.

Fixes golang/go#70233

Change-Id: Iacd85833dba91e870accf038e1c69a01e42fca1f
Reviewed-on: https://go-review.googlesource.com/c/tools/+/635226
LUCI-TryBot-Result: Go LUCI <[email protected]>
Reviewed-by: Robert Findley <[email protected]>

Author: adonovan

gopls/doc/release/v0.18.0.md

@@ -1,5 +1,7 @@
 # Configuration Changes
 
+- The experimental `hoverKind=Structured` setting is no longer supported.
+
 # New features
 
 ## "Implementations" supports generics

gopls/doc/settings.md

@@ -399,17 +399,13 @@ Default: `true`.
 ### `hoverKind enum`
 
 hoverKind controls the information that appears in the hover text.
-SingleLine and Structured are intended for use only by authors of editor plugins.
+SingleLine is intended for use only by authors of editor plugins.
 
 Must be one of:
 
 * `"FullDocumentation"`
 * `"NoDocumentation"`
 * `"SingleLine"`
-* `"Structured"` is an experimental setting that returns a structured hover format.
-This format separates the signature from the documentation, so that the client
-can do more manipulation of these fields.\
-This should only be used by clients that support this behavior.
 * `"SynopsisDocumentation"`
 
 Default: `"FullDocumentation"`.

gopls/internal/doc/api.json

@@ -95,7 +95,7 @@
 			{
 				"Name": "hoverKind",
 				"Type": "enum",
-				"Doc": "hoverKind controls the information that appears in the hover text.\nSingleLine and Structured are intended for use only by authors of editor plugins.\n",
+				"Doc": "hoverKind controls the information that appears in the hover text.\nSingleLine is intended for use only by authors of editor plugins.\n",
 				"EnumKeys": {
 					"ValueType": "",
 					"Keys": null
@@ -113,10 +113,6 @@
 						"Value": "\"SingleLine\"",
 						"Doc": ""
 					},
-					{
-						"Value": "\"Structured\"",
-						"Doc": "`\"Structured\"` is an experimental setting that returns a structured hover format.\nThis format separates the signature from the documentation, so that the client\ncan do more manipulation of these fields.\n\nThis should only be used by clients that support this behavior.\n"
-					},
 					{
 						"Value": "\"SynopsisDocumentation\"",
 						"Doc": ""