Allow docs browser thread to quit early

Author: timothyschoen

Source/Sidebar/DocumentationBrowser.h

@@ -242,10 +242,11 @@ class DocumentationBrowser : public Component, public FileDragAndDropTarget, pri
         static File versionDataDir = ProjectInfo::appDataDir.getChildFile("Versions");
         static File toolchainDir = ProjectInfo::appDataDir.getChildFile("Toolchain");
 
-        if (!directory.exists() || !directory.isDirectory() || directory == versionDataDir || directory == toolchainDir) {
-                return ValueTree();
+        if (threadShouldExit() || !directory.exists() || !directory.isDirectory() || directory == versionDataDir || directory == toolchainDir)
+        {
+            return ValueTree();
         }
-        
+                
         ValueTree rootNode("Folder");
         rootNode.setProperty("Name", directory.getFileName(), nullptr);
         rootNode.setProperty("Path", directory.getFullPathName(), nullptr);