[clangd] Add ':' to completion trigger characters.

Summary:
Without it we don't get completion requests from VSCode after
nested name qualifiers (e.g. after 'std::').

Reviewers: krasimir, bkramer

Reviewed By: krasimir

Subscribers: klimek, cfe-commits

Differential Revision: https://reviews.llvm.org/D35986

llvm-svn: 309550

clang-tools-extra/clangd/ClangdLSPServer.cpp

@@ -86,7 +86,7 @@ void ClangdLSPServer::LSPProtocolCallbacks::onInitialize(StringRef ID,
           "documentRangeFormattingProvider": true,
           "documentOnTypeFormattingProvider": {"firstTriggerCharacter":"}","moreTriggerCharacter":[]},
           "codeActionProvider": true,
-          "completionProvider": {"resolveProvider": false, "triggerCharacters": [".",">"]},
+          "completionProvider": {"resolveProvider": false, "triggerCharacters": [".",">",":"]},
           "definitionProvider": true
         }}})");
 }

clang-tools-extra/test/clangd/formatting.test

@@ -4,14 +4,14 @@
 Content-Length: 125
 
 {"jsonrpc":"2.0","id":0,"method":"initialize","params":{"processId":123,"rootPath":"clangd","capabilities":{},"trace":"off"}}
-# CHECK: Content-Length: 462
+# CHECK: Content-Length: 466
 # CHECK: {"jsonrpc":"2.0","id":0,"result":{"capabilities":{
 # CHECK:   "textDocumentSync": 1,
 # CHECK:   "documentFormattingProvider": true,
 # CHECK:   "documentRangeFormattingProvider": true,
 # CHECK:   "documentOnTypeFormattingProvider": {"firstTriggerCharacter":"}","moreTriggerCharacter":[]},
 # CHECK:   "codeActionProvider": true,
-# CHECK:   "completionProvider": {"resolveProvider": false, "triggerCharacters": [".",">"]},
+# CHECK:   "completionProvider": {"resolveProvider": false, "triggerCharacters": [".",">",":"]},
 # CHECK:   "definitionProvider": true
 # CHECK: }}}
 #