GN: Add -Wl,-z defs on linux and fix errors

chrome/renderer/BUILD.gn

 # Copyright 2014 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.
 
 import("//build/config/features.gni")
 import("//tools/grit/grit_rule.gni")
 
 gypi_values = exec_script("//build/gypi_to_gn.py",
                           [ rebase_path("../chrome_renderer.gypi") ],
                           "scope",
@@ skipping 101 matching lines @@
     deps += [
       # TODO(hclam): See crbug.com/298380 for details.
       # We should isolate the APIs needed by the renderer.
       "//chrome/common/extensions/api",
       "//extensions:extensions_resources",
       "//extensions/renderer",
       "//media/cast:net",
       "//media/cast:sender",
       "//media/cast/logging/proto",
     ]
+    if (!enable_webrtc) {
+      sources -= [
+        "media/cast_rtp_stream.cc",
+        "media/cast_rtp_stream.h",
+      ]
+    }
   }
   if (enable_webrtc) {
     sources +=
         rebase_path(gypi_values.chrome_renderer_webrtc_sources, ".", "..")
   }
   if (enable_extensions && enable_webrtc) {
     sources +=
         rebase_path(gypi_values.chrome_renderer_webrtc_extensions_sources,
                     ".",
                     "..")
@@ skipping 61 matching lines @@
     ]
   }
 
   if (enable_webrtc) {
     sources += [
       "media/mock_webrtc_logging_message_filter.cc",
       "media/mock_webrtc_logging_message_filter.h",
     ]
   }
 }