Re-commit optimization bisect support (r267022) without new pass manager support.

The original commit was reverted because of a buildbot problem with LazyCallGraph::SCC handling (not related to the OptBisect handling).

Differential Revision: http://reviews.llvm.org/D19172

llvm-svn: 267231
diff --git a/llvm/lib/Transforms/IPO/FunctionImport.cpp b/llvm/lib/Transforms/IPO/FunctionImport.cpp
index 25d4130..cb8d633 100644
--- a/llvm/lib/Transforms/IPO/FunctionImport.cpp
+++ b/llvm/lib/Transforms/IPO/FunctionImport.cpp
@@ -499,6 +499,9 @@
       : ModulePass(ID), Index(Index) {}
 
   bool runOnModule(Module &M) override {
+    if (skipModule(M))
+      return false;
+
     if (SummaryFile.empty() && !Index)
       report_fatal_error("error: -function-import requires -summary-file or "
                          "file from frontend\n");