RFR: JDK-8153969: Clean up module src dir logic

[Magnus Ihse Bursie]

Looks great! Nice cleanup/abstraction. 

By "multiple" calls, you mean nested calls, not concatenated. This was not immediately clear to me. Maybe clarify that in the comment to PathList. Also, it mentions -classpath but this applies to modulepath as well. 

/Magnus

> 12 apr. 2016 kl. 15:44 skrev Erik Joelsson <erik.joelsson at oracle.com>:
> 
> This failed on Windows in the workaround for jdk.vm.ci modulesourcepath. Here is a new version where I made the PathList macro safe for multiple calls. I also added a test to verify this behavior.
> 
> http://cr.openjdk.java.net/~erikj/8153969/webrev.top.03/
> 
> /Erik
> 
>> On 2016-04-12 14:37, Erik Joelsson wrote:
>> New webrev with some more cleanup in CompileJavaModules.gmk. Fixed the variable name and also realized that the call to MakeDir was no longer necessary. Starting to look pretty neat.
>> 
>> http://cr.openjdk.java.net/~erikj/8153969/webrev.top.02/
>> 
>> /Erik
>> 
>>> On 2016-04-12 11:37, Erik Joelsson wrote:
>>> That is a good point, I will clean up that naming too.
>>> 
>>> /Erik
>>> 
>>>> On 2016-04-11 18:26, Jonathan Gibbons wrote:
>>>>> On 04/11/2016 05:28 AM, Erik Joelsson wrote:
>>>>> We currently have 3 places in the makefiles where the full list of source dirs for each module is calculated. I have refactored this into macros in make/common/Modules.gmk so that it's handled uniformly. This will also make it simpler for other potential users of this data, like IDE project generation.
>>>>> 
>>>>> Bug: https://bugs.openjdk.java.net/browse/JDK-8153969
>>>>> Webrev: http://cr.openjdk.java.net/~erikj/8153969/webrev.top.01/
>>>>> 
>>>>> /Erik
>>>> 
>>>> In a world where we are trying to differentiate betwen module paths and class paths, the name MODULECLASSPATH seems somewhat schizophrenic.
>>>> 
>>>> -- Jon
>