qt: define QT_NO_KEYWORDS

QT_NO_KEYWORDS prevents Qt from defining the `foreach`, `signals`,
`slots` and `emit` macros.

Avoid overlap between Qt macros and boost - for example #undef hackiness
in #6421.

src/qt/bitcoin.cpp

@@ -169,11 +169,11 @@ class BitcoinCore: public QObject
 public:
     explicit BitcoinCore();
 
-public slots:
+public Q_SLOTS:
     void initialize();
     void shutdown();
 
-signals:
+Q_SIGNALS:
     void initializeResult(int retval);
     void shutdownResult(int retval);
     void runawayException(const QString &message);
@@ -216,13 +216,13 @@ public:
     /// Get window identifier of QMainWindow (BitcoinGUI)
     WId getMainWinId() const;
 
-public slots:
+public Q_SLOTS:
     void initializeResult(int retval);
     void shutdownResult(int retval);
     /// Handle runaway exceptions. Shows a message box with the problem and quits the program.
     void handleRunawayException(const QString &message);
 
-signals:
+Q_SIGNALS:
     void requestedInitialize();
     void requestedShutdown();
     void stopThread();
@@ -253,7 +253,7 @@ BitcoinCore::BitcoinCore():
 void BitcoinCore::handleRunawayException(const std::exception *e)
 {
     PrintExceptionContinue(e, "Runaway exception");
-    emit runawayException(QString::fromStdString(strMiscWarning));
+    Q_EMIT runawayException(QString::fromStdString(strMiscWarning));
 }
 
 void BitcoinCore::initialize()
@@ -269,7 +269,7 @@ void BitcoinCore::initialize()
              */
             StartDummyRPCThread();
         }
-        emit initializeResult(rv);
+        Q_EMIT initializeResult(rv);
     } catch (const std::exception& e) {
         handleRunawayException(&e);
     } catch (...) {
@@ -286,7 +286,7 @@ void BitcoinCore::shutdown()
         threadGroup.join_all();
         Shutdown();
         qDebug() << __func__ << ": Shutdown finished";
-        emit shutdownResult(1);
+        Q_EMIT shutdownResult(1);
     } catch (const std::exception& e) {
         handleRunawayException(&e);
     } catch (...) {
@@ -315,7 +315,7 @@ BitcoinApplication::~BitcoinApplication()
     if(coreThread)
     {
         qDebug() << __func__ << ": Stopping thread";
-        emit stopThread();
+        Q_EMIT stopThread();
         coreThread->wait();
         qDebug() << __func__ << ": Stopped thread";
     }
@@ -386,7 +386,7 @@ void BitcoinApplication::requestInitialize()
 {
     qDebug() << __func__ << ": Requesting initialize";
     startThread();
-    emit requestedInitialize();
+    Q_EMIT requestedInitialize();
 }
 
 void BitcoinApplication::requestShutdown()
@@ -409,7 +409,7 @@ void BitcoinApplication::requestShutdown()
     ShutdownWindow::showShutdownWindow(window);
 
     // Request shutdown from core thread
-    emit requestedShutdown();
+    Q_EMIT requestedShutdown();
 }
 
 void BitcoinApplication::initializeResult(int retval)
@@ -449,7 +449,7 @@ void BitcoinApplication::initializeResult(int retval)
         {
             window->show();
         }
-        emit splashFinished(window);
+        Q_EMIT splashFinished(window);
 
 #ifdef ENABLE_WALLET
         // Now that initialization/startup is done, process any command-line