Modularize the build.
1. Add -DLINE_SEARCH_MINIMIZER to CMake to make the line search
minimizer optional.
2. Better handling of -DSUITESPARSE/-DCXSPARSE in top level cmake
file.
3. Disable code which will never be used if SuiteSparse and/or
CXSparse is not available.
4. Update build docs.
5. Update jni/Android.mk
6. Minor lint cleanup from William Rucklidge.
Change-Id: If60460a858000df82faed7a6bb056dd2bfdde562
diff --git a/internal/ceres/visibility.h b/internal/ceres/visibility.h
index f29e3c6..2d1e6f8 100644
--- a/internal/ceres/visibility.h
+++ b/internal/ceres/visibility.h
@@ -35,6 +35,8 @@
#ifndef CERES_INTERNAL_VISIBILITY_H_
#define CERES_INTERNAL_VISIBILITY_H_
+#ifndef CERES_NO_SUITESPARSE
+
#include <set>
#include <vector>
#include "ceres/graph.h"
@@ -74,4 +76,5 @@
} // namespace internal
} // namespace ceres
+#endif // CERES_NO_SUITESPARSE
#endif // CERES_INTERNAL_VISIBILITY_H_
