It's not documented, and it does nothing unless CMake 2.0 compatibility
is enabled (and it isn't):

https://github.com/Kitware/CMake/blob/v2.6.0/Source/cmConfigureFileCommand.cxx

If it's followed by a slash and OpenCV_INSTALL_BINARIES_PREFIX is empty,
then the resulting path becomes absolute.

Fixes <http://code.opencv.org/issues/3350>.

Allow to build samples via OpenCV binaries from distribution package
(find_package with OpenCV_DIR).

Solve the problem seen when using recent versions of CMake (such as 2.8.11): OpenCVConfig.cmake violates the policy CMP0004.

Symptoms:
CMake Error at CMakeLists.txt:10 (add_executable):
Target "my_app" links to item "C:/Program Files " which has leading
or trailing whitespace. This is now an error according to policy CMP0004.

This problem occurs when building on Windows when we depend on libraries located (for example) in "C:\Program Files (x86)..."

* fix path to libraries in Android SDK
* allow to link to opencv_java.so as Android.mk does

To link to opencv_java.so you can either change your cmake to find OpenCV as

    find_package(OpenCV opencv_java)

or pass -DOpenCV_FIND_COMPONENTS=opencv_java to your cmake command

Better variant of OpenCVConfig.cmake generation; several smaller changes in the options section and Android build scripts

 [~] Automatically tracked dependencies between modules
 [+] Support for optional module dependencies
 [+] Options to choose modules to build
 [~] Removed hardcoded modules lists from OpenCVConfig.cmake, opencv.pc and OpenCV.mk
 [+] Added COMPONENTS support for FIND_PACKAGE(OpenCV)
 [~] haartraining and traincascade are moved outside of modules folder since they aren't the modules