install: Add EXCLUDE_FROM_ALL option (#14921)

Let us take an example of a project that has some tests in a component
that need to be installed into a dedicated test package.  The user
expectation is that the result could be achieved by typing the
following:

    make
    make tests
    make install
    DESTDIR=/testpkgs make install-tests

However this results in test components in the default installation as
well as the testpkg.

Add an EXCLUDE_FROM_ALL option to the install() command to tell it that
the installation rule should not be included unless its component is
explicitly specified for installation.

1 files changed, 1 insertions, 0 deletions

diff --git a/Source/cmInstallExportGenerator.h b/Source/cmInstallExportGenerator.h
index 885ed0596a..1b1c046c16 100644
--- a/Source/cmInstallExportGenerator.h
+++ b/Source/cmInstallExportGenerator.h
@@ -31,6 +31,7 @@ public:
                            const std::vector<std::string>& configurations,
                            const char* component,
                            MessageLevel message,
+                           bool exclude_from_all,
                            const char* filename, const char* name_space,
                            bool exportOld);
   ~cmInstallExportGenerator();