Always treat all sources as parts of the module being compiled

If a path to the module-info.java file is passed as an argument, we
should treat all other source files passed as arguments (either as
individual source files or inside a source directory) as members of that
module. Previously we treated other source files as members of the
unnamed module, and this resulted in incorrect errors when using a
member exported with a qualification from another named module, for
example

 #KT-18598 In Fixed

compiler/testData/javaModules/specifyPathToModuleInfoInArguments/moduleB/usage.kt

@@ -0,0 +1,14 @@
+import foo.Foo
+import unexported.Unexported
+
+fun usage() {
+    // Should be OK
+    Foo()
+
+    // Should be error
+    Unexported()
+
+    // Should be error: if we're passing the path to a particular module-info.java to the compiler,
+    // we should not treat its location as a root
+    Unrelated()
+}