By inserting the necessary checks for null inside the callee
at the AST level, the code generation of == operations can be
greatly simplified.
This is a performance-neutral change and a step for allowing
generic inlining of arbitrary == methods. So far we could only
inline them for a common set of types in the flow graph
optimizer.
R=srdjan@google.com
Review URL: https://codereview.chromium.org//24203004
git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@28084 260f80e4-7a28-3924-810f-c04153c831b5