Move plugin placeholder style to CSS, and allow it to bypass main world CSP.

public/blink_resources.grd

 <?xml version="1.0" encoding="UTF-8"?>
 <grit latest_public_release="0" current_release="1">
   <outputs>
     <output filename="grit/blink_resources.h" type="rc_header">
       <emit emit_type='prepend'></emit>
     </output>
     <output filename="blink_resources.rc" type="rc_all" />
     <output filename="blink_resources.pak" type="data_package" />
   </outputs>
   <release seq="1">
@@ skipping 25 matching lines @@
       <include name="IDR_UASTYLE_VIEWPORT_ANDROID_CSS" file="../Source/core/css/viewportAndroid.css" type="BINDATA"/>
 
       <include name="IDR_INSPECTOR_OVERLAY_PAGE_HTML" file="../Source/core/inspector/InspectorOverlayPage.html" type="BINDATA"/>
       <include name="IDR_INSPECTOR_INJECTED_SCRIPT_CANVAS_MODULE_SOURCE_JS" file="../Source/core/inspector/InjectedScriptCanvasModuleSource.js" type="BINDATA"/>
       <include name="IDR_INSPECTOR_INJECTED_SCRIPT_SOURCE_JS" file="../Source/core/inspector/InjectedScriptSource.js" type="BINDATA"/>
       <include name="IDR_INSPECTOR_DEBUGGER_SCRIPT_SOURCE_JS" file="../Source/bindings/core/v8/DebuggerScript.js" type="BINDATA"/>
       <include name="IDR_PRIVATE_SCRIPT_DOCUMENTXMLTREEVIEWER_JS" file="../Source/core/xml/DocumentXMLTreeViewer.js" type="BINDATA"/>
       <include name="IDR_PRIVATE_SCRIPT_HTMLMARQUEEELEMENT_JS" file="../Source/core/html/HTMLMarqueeElement.js" type="BINDATA"/>
       <include name="IDR_PRIVATE_SCRIPT_PLUGINPLACEHOLDERELEMENT_JS" file="../Source/core/html/shadow/PluginPlaceholderElement.js" type="BINDATA"/>
       <include name="IDR_PRIVATE_SCRIPT_PRIVATESCRIPTRUNNER_JS" file="../Source/bindings/core/v8/PrivateScriptRunner.js" type="BINDATA"/>
+      <include name="IDR_PRIVATE_STYLE_PLUGINPLACEHOLDERELEMENT_CSS" file="../Source/core/html/shadow/PluginPlaceholderElement.css" type="BINDATA"/>
       <include name="IDR_PICKER_COMMON_JS" file="../Source/web/resources/pickerCommon.js" type="BINDATA"/>
       <include name="IDR_PICKER_COMMON_CSS" file="../Source/web/resources/pickerCommon.css" type="BINDATA"/>
       <include name="IDR_CALENDAR_PICKER_CSS" file="../Source/web/resources/calendarPicker.css" type="BINDATA"/>
       <include name="IDR_CALENDAR_PICKER_JS" file="../Source/web/resources/calendarPicker.js" type="BINDATA"/>
       <include name="IDR_PICKER_BUTTON_CSS" file="../Source/web/resources/pickerButton.css" type="BINDATA"/>
       <include name="IDR_SUGGESTION_PICKER_CSS" file="../Source/web/resources/suggestionPicker.css" type="BINDATA"/>
       <include name="IDR_SUGGESTION_PICKER_JS" file="../Source/web/resources/suggestionPicker.js" type="BINDATA"/>
       <include name="IDR_COLOR_SUGGESTION_PICKER_CSS" file="../Source/web/resources/colorSuggestionPicker.css" type="BINDATA"/>
       <include name="IDR_COLOR_SUGGESTION_PICKER_JS" file="../Source/web/resources/colorSuggestionPicker.js" type="BINDATA"/>
       <if expr="pp_ifdef('use_concatenated_impulse_responses')">
@@ skipping 237 matching lines @@
         <include name="IDR_AUDIO_SPATIALIZATION_T345_P060" file="..\Source\platform\audio\resources\IRC_Composite_C_R0195_T345_P060.wav" type="BINDATA"/>
         <include name="IDR_AUDIO_SPATIALIZATION_T345_P075" file="..\Source\platform\audio\resources\IRC_Composite_C_R0195_T345_P075.wav" type="BINDATA"/>
         <include name="IDR_AUDIO_SPATIALIZATION_T345_P090" file="..\Source\platform\audio\resources\IRC_Composite_C_R0195_T345_P090.wav" type="BINDATA"/>
         <include name="IDR_AUDIO_SPATIALIZATION_T345_P315" file="..\Source\platform\audio\resources\IRC_Composite_C_R0195_T345_P315.wav" type="BINDATA"/>
         <include name="IDR_AUDIO_SPATIALIZATION_T345_P330" file="..\Source\platform\audio\resources\IRC_Composite_C_R0195_T345_P330.wav" type="BINDATA"/>
         <include name="IDR_AUDIO_SPATIALIZATION_T345_P345" file="..\Source\platform\audio\resources\IRC_Composite_C_R0195_T345_P345.wav" type="BINDATA"/>
       </if>
     </includes>
   </release>
 </grit>