media: Set RUNPATH in cdm adapter in GN component build

media/cdm/ppapi/ppapi_cdm_adapter.gni

 # Copyright 2015 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # This template defines a CDM adapter target. Just use this as you would a
 # normal target and everything should work correctly. If GYP, you would instead
 # depend on media/media_cdm_adapter.gyp:cdmadapter which would in turn modify
 # your target with direct_dependent_settings.
 template("ppapi_cdm_adapter") {
   if (is_mac || is_linux) {
@@ skipping 41 matching lines @@
       ]
 
       output_extension = "plugin"
     } else if (is_posix) {
       cflags += [ "-fvisibility=hidden" ]
 
       # Required for clock_gettime()
       libs += [ "rt" ]
     }
 
-    if (is_linux && !is_component_build) {
-      # CDM adapter depends on a CDM even in non-component builds.
+    if (is_linux) {
+      # CDM adapter depends on a CDM in component and non-component builds.
       configs += [ "//build/config/gcc:rpath_for_built_shared_libraries" ]

[ddorwin, 2016/05/16 18:11:12]

I know we need to set rpath for the adapter, but two things:
1. The warning not to use this for release builds:
https://code.google.com/p/chromium/codesearch#chromium/src/build/config/gcc/B...
2. It seems this isn't intended to do what we want (bind to the same directory).
If shlib_subdir was set, I don't think this would do what we want.

[xhwang, 2016/05/16 18:23:07]

This was discussed when we added this back. See
https://bugs.chromium.org/p/chromium/issues/detail?id=583009#c18
Good point. Maybe we should just manually set rpath here? I don't know what's
the plan to use a separate shlib_subdir for GN. At some point when we deprecate
cdm adapters this problem will go away.

[ddorwin, 2016/05/16 18:28:46]

thestig@: Should we update the documentation in the source link above?
If possible, that would be best. If not, then we'll just have to live with it
until then.

[Lei Zhang, 2016/05/17 20:31:15]

Meh. The config("executable_ldconfig") section in build/config/gcc/BUILD.gn
normally already takes caer of the component build case. ppapi_cdm_adapter is
probably one of the few exceptions.

     }
 
     # TODO(jschuh) crbug.com/167187
     configs += [ "//build/config/compiler:no_size_t_to_int_warning" ]
   }
 }