3 invocations of hook_module_implements_alter()

drupal_alter in includes/module.inc: Passes alterable variables to specific hook_TYPE_alter() implementations.
ModuleImplementsAlterTestCase::testModuleImplementsAlter in modules/simpletest/tests/module.test: Tests hook_module_implements_alter() adding an implementation.
module_implements in includes/module.inc: Determines which modules are implementing a hook.

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