Update comment in trust_region_minimizer.h.

Update comment to better reflect the Minimizer API.

Change-Id: Icca1d41fdea1f8dacde2e1af3239486820ef2b7f

internal/ceres/trust_region_minimizer.h

diff --git a/internal/ceres/trust_region_minimizer.h b/internal/ceres/trust_region_minimizer.h
index a4f5ba3..49f5733 100644
--- a/internal/ceres/trust_region_minimizer.h
+++ b/internal/ceres/trust_region_minimizer.h
@@ -39,8 +39,7 @@
 namespace internal {
 
 // Generic trust region minimization algorithm. The heavy lifting is
-// done by a TrustRegionStrategy object passed in as one of the
-// arguments to the Minimize method.
+// done by a TrustRegionStrategy object passed in as part of options.
 //
 // For example usage, see SolverImpl::Minimize.
 class TrustRegionMinimizer : public Minimizer {