fix EA java.lang.IllegalArgumentException: Argument 1 for @NotNull parameter of com/intellij/ide/browsers/UrlImpl.<init> must not be null
    	at com.intellij.ide.browsers.UrlImpl.<init>(UrlImpl.java:-1)
    	at com.intellij.ide.browsers.Urls.parseUrl(Urls.java:75)
    	at com.intellij.ide.browsers.Urls.parse(Urls.java:40)
    	at com.jetbrains.javascript.debugger.JsFileUtil.isOnBuiltInWebServer(JsFileUtil.java:64)
    	at com.intellij.javascript.debugger.execution.JavaScriptDebugSettingsEditor$1.textChanged(JavaScriptDebugSettingsEditor.java:112)
start offset calculation needs no locking
fix project leak from PsiBuilderQuickTest