LanguageClient: Add signal to inform about WorkDoneProgressEnd

... and make use of it in the clangd client to be able tell when
background indexing has finished.

Change-Id: I0f3c6f9646fd66ababd08c12b2f347da5f1a3729
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/languageclient/client.cpp

@@ -1250,6 +1250,8 @@ void Client::handleMethod(const QString &method, const MessageId &id, const ICon
             if (!params->isValid())
                 logError(*params);
             m_progressManager.handleProgress(*params);
+            if (ProgressManager::isProgressEndMessage(*params))
+                emit workDone(params->token());
         }
     } else if (id.isValid()) {
         Response<JsonObject, JsonObject> response(id);

src/plugins/languageclient/client.h

@@ -178,6 +178,7 @@ signals:
     void initialized(const LanguageServerProtocol::ServerCapabilities &capabilities);
     void capabilitiesChanged(const DynamicCapabilities &capabilities);
     void documentUpdated(TextEditor::TextDocument *document);
+    void workDone(const LanguageServerProtocol::ProgressToken &token);
     void finished();
 
 protected:

src/plugins/languageclient/progressmanager.cpp

@@ -61,6 +61,11 @@ void ProgressManager::setTitleForToken(const LanguageServerProtocol::ProgressTok
     m_titles.insert(token, message);
 }
 
+bool ProgressManager::isProgressEndMessage(const LanguageServerProtocol::ProgressParams &params)
+{
+    return Utils::holds_alternative<WorkDoneProgressEnd>(params.value());
+}
+
 Utils::Id languageClientProgressId(const ProgressToken &token)
 {
     constexpr char k_LanguageClientProgressId[] = "LanguageClient.ProgressId.";

src/plugins/languageclient/progressmanager.h

@@ -49,6 +49,8 @@ public:
     void setTitleForToken(const LanguageServerProtocol::ProgressToken &token,
                           const QString &message);
 
+    static bool isProgressEndMessage(const LanguageServerProtocol::ProgressParams &params);
+
 private:
     void beginProgress(const LanguageServerProtocol::ProgressToken &token,
                        const LanguageServerProtocol::WorkDoneProgressBegin &begin);