Add descriptions with examples to run-blink-* scripts.

third_party/WebKit/Tools/Scripts/run-blink-httpd

Index: third_party/WebKit/Tools/Scripts/run-blink-httpd
diff --git a/third_party/WebKit/Tools/Scripts/run-blink-httpd b/third_party/WebKit/Tools/Scripts/run-blink-httpd
index a3a01a4d5468999151a7e766f2c752de1b1fce67..7d7701b101a05bea8115e2e04e98f8fe8dabdae8 100755
--- a/third_party/WebKit/Tools/Scripts/run-blink-httpd
+++ b/third_party/WebKit/Tools/Scripts/run-blink-httpd
@@ -27,9 +27,29 @@
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+"""Runs an Apache HTTP server to manually run layout tests locally.
+
+After running this script, you can locally navigate to URLs where
+the path is relative to LayoutTests/http/tests/. For example, to run
+LayoutTests/http/tests/cachestorage/window-cache-add.html, navigate to:
+    http://127.0.0.1:8000/cachestorage/window/cache-add.html
+
+When using HTTPS, for example:
+    https://127.0.0.1:8443/https/verify-ssl-enabled.php
+you will may a certificate warning, which you need to bypass.
+
+After starting the server, you can also run individual layout tests
+via content_shell, e.g.
+    $ out/Release/content_shell --run-layout-test \
+    http://127.0.0.1:8000/security/cross-frame-access-get.html
+
+Note that some tests will only work if "127.0.0.1" for the host part of the
+URL, rather than "localhost".
+"""
+
 import webkitpy.common.version_check
 
 from webkitpy.layout_tests.servers import cli_wrapper
 from webkitpy.layout_tests.servers import apache_http
 
-cli_wrapper.main(apache_http.ApacheHTTP, additional_dirs={}, number_of_servers=4)
+cli_wrapper.main(apache_http.ApacheHTTP, additional_dirs={}, number_of_servers=4, description=__doc__)