Merging r228118:

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r228118 | sameer.sahasrabuddhe | 2015-02-04 01:38:18 -0500 (Wed, 04 Feb 2015) | 8 lines

OpenCL: handle ternary operator when the condition is a vector

When the condition is a vector, OpenCL specifies additional
requirements on the operand types, and also the operations
required to determine the result type of the operator. This is a
combination of OpenCL v1.1 s6.3.i and s6.11.6, and the semantics
remain unchanged in later versions of OpenCL.

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llvm-svn: 240324