Compiler: Test fail on non english system

[Rileran]

I am using a french system (LANG FR_fr) and I got into trouble trying to run tests on the Compiler project. The test messages are compared against localized message, therefore making test case fail.

Example in ASPrrivateConstructorTests, test testConstructorMustBePublicProblem_withInternalConstructor_andAllowPrivateConstructorsDisabled

[ERROR]   ASPrivateConstructorTests.testConstructorMustBePublicProblem_withInternalConstructor_andAllowPrivateConstructorsDisabled:110->ASFeatureTestsBase.compileAndExpectErrors:175 
Expected: is "A constructor can only be declared public\n"
     got: "Un constructeur ne peut être déclaré que public.\n"

This can be easily fix by setting this variable to EN_us, but maybe this should be a default in the test configuration.

I have tried adding configuration to the maven-surefire-plugin without success. What I have tried so far (in compiler/pom.xml) :

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-surefire-plugin</artifactId>
    <configuration>
      <environmentVariables>
        <LANG>en_US</LANG>
      </environmentVariables>
  ...
</plugin>

and

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-surefire-plugin</artifactId>
    <configuration>
      <systemPropertyVariables>
        <user.language>en</user.language>
        <user.country>US</user.country>
      </systemPropertyVariables>
  ...
</plugin>

and

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-surefire-plugin</artifactId>
    <configuration>
      <argLine>-Duser.language=en -Duser.country=US</argline>
  ...
</plugin>

Maybe there is something that I am missing here.