Remove enable_media_router.

chrome/browser/browser_resources.grd

 <?xml version="1.0" encoding="UTF-8"?>
 <grit latest_public_release="0" current_release="1" output_all_resource_defines="false">
   <outputs>
     <output filename="grit/browser_resources.h" type="rc_header">
       <emit emit_type='prepend'></emit>
     </output>
     <output filename="browser_resources.pak" type="data_package" />
   </outputs>
   <release seq="1">
     <structures>
@@ skipping 606 matching lines @@
             <include name="IDR_M17N_MANIFEST" file="resources\chromeos\input_method\m17n_manifest.json" type="BINDATA" />
             <include name="IDR_PINYIN_MANIFEST" file="resources\chromeos\input_method\pinyin_manifest.json" type="BINDATA" />
             <include name="IDR_ZHUYIN_MANIFEST" file="resources\chromeos\input_method\zhuyin_manifest.json" type="BINDATA" />
             <include name="IDR_CANGJIE_MANIFEST" file="resources\chromeos\input_method\cangjie_manifest.json" type="BINDATA" />
             <include name="IDR_MOZC_MANIFEST" file="resources\chromeos\input_method\mozc_manifest.json" type="BINDATA" />
             <include name="IDR_HANGUL_MANIFEST" file="resources\chromeos\input_method\hangul_manifest.json" type="BINDATA" />
           </else>
         </if>
         <include name="IDR_BRAILLE_MANIFEST" file="resources\chromeos\braille_ime\manifest.json" type="BINDATA" />
       </if>
-      <if expr="enable_media_router">
-        <part file="media_router_resources.grdp" />
-      </if>
-      <if expr="enable_media_router and (chromeos or is_win or is_macosx)">
+      <part file="media_router_resources.grdp" />
+      <if expr="chromeos or is_win or is_macosx">
         <include name="IDR_CAST_HTML" file="resources\cast\cast.html" type="BINDATA" />
         <include name="IDR_CAST_CSS" file="resources\cast\cast.css" type="BINDATA" />
         <include name="IDR_CAST_JS" file="resources\cast\cast.js" type="BINDATA" />
         <include name="IDR_CAST_FAVICON" file="resources\cast\cast_favicon.ico" type="BINDATA" />
       </if>
       <if expr="not is_android and not is_ios">
         <include name="IDR_IME_WINDOW_CLOSE" file="resources\input_ime\ime_window_close.png" type="BINDATA" />
         <include name="IDR_IME_WINDOW_CLOSE_C" file="resources\input_ime\ime_window_close_click.png" type="BINDATA" />
         <include name="IDR_IME_WINDOW_CLOSE_H" file="resources\input_ime\ime_window_close_hover.png" type="BINDATA" />
       </if>
@@ skipping 16 matching lines @@
       <if expr="not is_android and not is_ios">
         <include name="IDR_SSL_ERROR_ASSISTANT_PB" file="${root_gen_dir}/chrome/browser/resources/ssl/ssl_error_assistant/ssl_error_assistant.pb" use_base_dir="false" type="BINDATA" />
       </if>
       <if expr="is_android or is_linux">
         <include name="IDR_SANDBOX_INTERNALS_HTML" file="resources\sandbox_internals\sandbox_internals.html" flattenhtml="true" allowexternalscript="true" type="BINDATA" compress="gzip" />
         <include name="IDR_SANDBOX_INTERNALS_JS" file="resources\sandbox_internals\sandbox_internals.js" type="BINDATA" compress="gzip" />
       </if>
     </includes>
   </release>
 </grit>