GWT Eclipse Plugin and Update Maven Project

Hi,

there is minimal project which reproduces behavior described below. Project is empty. All dependencies are removed, but project pom file, except dependencies is unchanged from real project. It compiles with maven. When it is imported into eclipse, it recognizes module as Web application and GWT module.
Initially "This project has WAR directory" is checked, and "Launch and deploy from this directory (disabled because this is a Maven project)" is unchecked, but enabled. If I check this checkbox, setting lasts only until I refresh project with "Update Maven Project". After update this checkbox becomes unchecked.

from mailing list(https://groups.google.com/forum/#!topic/google-web-toolkit/c9AD8XZC1pw):

I observe one problem of GWT Eclipse Plugin(3.0.0.201610212207) when using it with maven project.

Debugging works very well.

But:
- my project contains WAR directory, and GWT project setting "This project has WAR directory" (src/main/webapp) is checked.
- GWT debug configuration arguments contain -war ...../src/main/webapp.
- when I check GWT project setting "Launch and deploy from this directory (disabled because this is a Maven project)" - everything works perfectly.

Problem occurs when I Update Maven Project (Alt+F5).

Then GWT project setting "Launch and deploy from this directory (disabled because this is a Maven project)" is unchecked and more unpleasant - when launching debugger something cleans this directory - removes web.xml, static resources etc.

[ttt.zip](https://github.com/gwt-plugins/gwt-eclipse-plugin/files/551587/ttt.zip)

Comienza con el proyecto Maven mínimo adjunto y su pom.xml; impórtalo en Eclipse, habilita la GWT WAR-directory launch setting y, después, ejecuta Update Maven Project (Alt+F5). Compara la configuración y src/main/webapp antes y después; se considera terminado cuando la configuración sigue habilitada y el directorio no se limpia.

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