Issue 10985 - Compiler doesn't attempt to inline non-templated functions from libraries (even having the full source)

http://d.puremagic.com/issues/show_bug.cgi?id=10985

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This PR requires druntime fix: https://github.com/D-Programming-Language/druntime/pull/608

Today, implicitly generated code for assertions/array-bounds-check uses ModuleInfo object.
However `ModuleInfo` object won't be generated if the module is not in root - even though the code in module could be directly used by template instantiation and/or inlining.

To fix the issues:
1. Stop using ModuleInfo for assertion and array bounds check.
2. Relax the condition for inlining, due to fix bug 10985.
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During the work, I found a wrong-code [bug 11049](http://d.puremagic.com/issues/show_bug.cgi?id=11049), and this PR also fixes it.
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