Plugin Placeholders: Refactor for platforms that don't support plugins

components/plugins/renderer/loadable_plugin_placeholder.cc

 // 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.
 
 #include "components/plugins/renderer/loadable_plugin_placeholder.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
 #include "base/json/string_escape.h"
 #include "base/strings/string_piece.h"
-#include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/values.h"
 #include "content/public/child/v8_value_converter.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/renderer/render_frame.h"
 #include "content/public/renderer/render_thread.h"
 #include "gin/handle.h"
 #include "gin/object_template_builder.h"
 #include "third_party/WebKit/public/web/WebDOMMessageEvent.h"
 #include "third_party/WebKit/public/web/WebDocument.h"
 #include "third_party/WebKit/public/web/WebElement.h"
 #include "third_party/WebKit/public/web/WebInputEvent.h"
 #include "third_party/WebKit/public/web/WebKit.h"
 #include "third_party/WebKit/public/web/WebLocalFrame.h"
 #include "third_party/WebKit/public/web/WebPluginContainer.h"
 #include "third_party/WebKit/public/web/WebScriptSource.h"
 #include "third_party/WebKit/public/web/WebSerializedScriptValue.h"
 #include "third_party/WebKit/public/web/WebView.h"
-#include "third_party/re2/re2/re2.h"
 
 using base::UserMetricsAction;
-using blink::WebElement;
-using blink::WebLocalFrame;
-using blink::WebMouseEvent;
-using blink::WebNode;
-using blink::WebPlugin;
-using blink::WebPluginContainer;
-using blink::WebPluginParams;
-using blink::WebScriptSource;
-using blink::WebURLRequest;
 using content::PluginInstanceThrottler;
 using content::RenderThread;
 
 namespace plugins {
 
-#if defined(ENABLE_PLUGINS)
 void LoadablePluginPlaceholder::BlockForPowerSaverPoster() {
   DCHECK(!is_blocked_for_power_saver_poster_);
   is_blocked_for_power_saver_poster_ = true;
 
   render_frame()->RegisterPeripheralPlugin(
       GURL(GetPluginParams().url).GetOrigin(),
       base::Bind(&LoadablePluginPlaceholder::MarkPluginEssential,
                  weak_factory_.GetWeakPtr(),
                  PluginInstanceThrottler::UNTHROTTLE_METHOD_BY_WHITELIST));
 }
 
 void LoadablePluginPlaceholder::SetPremadePlugin(
     content::PluginInstanceThrottler* throttler) {
   DCHECK(throttler);
   DCHECK(!premade_throttler_);
   premade_throttler_ = throttler;
 }
-#endif
 
 LoadablePluginPlaceholder::LoadablePluginPlaceholder(
     content::RenderFrame* render_frame,
-    WebLocalFrame* frame,
-    const WebPluginParams& params,
-    const std::string& html_data,
-    GURL placeholderDataUrl)
-    : PluginPlaceholder(render_frame,
-                        frame,
-                        params,
-                        html_data,
-                        placeholderDataUrl),
+    blink::WebLocalFrame* frame,
+    const blink::WebPluginParams& params,
+    const std::string& html_data)
+    : PluginPlaceholder(render_frame, frame, params, html_data),
       is_blocked_for_background_tab_(false),
       is_blocked_for_prerendering_(false),
       is_blocked_for_power_saver_poster_(false),
       power_saver_enabled_(false),
       premade_throttler_(nullptr),
-      allow_loading_(false),
-      hidden_(false),
+      allow_loading_(true),
       finished_loading_(false),
       weak_factory_(this) {
 }
 
 LoadablePluginPlaceholder::~LoadablePluginPlaceholder() {
 }
 
-#if defined(ENABLE_PLUGINS)
 void LoadablePluginPlaceholder::MarkPluginEssential(
     PluginInstanceThrottler::PowerSaverUnthrottleMethod method) {
   if (!power_saver_enabled_)
     return;
 
   power_saver_enabled_ = false;
 
   if (premade_throttler_)
     premade_throttler_->MarkPluginEssential(method);
   else
     PluginInstanceThrottler::RecordUnthrottleMethodMetric(method);
 
   if (is_blocked_for_power_saver_poster_) {
     is_blocked_for_power_saver_poster_ = false;
     if (!LoadingBlocked())
       LoadPlugin();
   }
 }
-#endif
-
-void LoadablePluginPlaceholder::BindWebFrame(blink::WebFrame* frame) {
-  v8::Isolate* isolate = blink::mainThreadIsolate();
-  v8::HandleScope handle_scope(isolate);
-  v8::Local<v8::Context> context = frame->mainWorldScriptContext();
-  DCHECK(!context.IsEmpty());
-
-  v8::Context::Scope context_scope(context);
-  v8::Local<v8::Object> global = context->Global();
-  global->Set(gin::StringToV8(isolate, "plugin"),
-              gin::CreateHandle(isolate, this).ToV8());
-}
 
 gin::ObjectTemplateBuilder LoadablePluginPlaceholder::GetObjectTemplateBuilder(
     v8::Isolate* isolate) {
-  return gin::Wrappable<PluginPlaceholder>::GetObjectTemplateBuilder(isolate)
+  return PluginPlaceholder::GetObjectTemplateBuilder(isolate)
       .SetMethod("load", &LoadablePluginPlaceholder::LoadCallback)
-      .SetMethod("hide", &LoadablePluginPlaceholder::HideCallback)
       .SetMethod("didFinishLoading",
                  &LoadablePluginPlaceholder::DidFinishLoadingCallback);
 }
 
-void LoadablePluginPlaceholder::ReplacePlugin(WebPlugin* new_plugin) {
+void LoadablePluginPlaceholder::ReplacePlugin(blink::WebPlugin* new_plugin) {
   CHECK(plugin());
   if (!new_plugin)
     return;
-  WebPluginContainer* container = plugin()->container();
+  blink::WebPluginContainer* container = plugin()->container();
   // Set the new plugin on the container before initializing it.
   container->setPlugin(new_plugin);
   // Save the element in case the plugin is removed from the page during
   // initialization.
-  WebElement element = container->element();
+  blink::WebElement element = container->element();
   bool plugin_needs_initialization =
       !premade_throttler_ || new_plugin != premade_throttler_->GetWebPlugin();
   if (plugin_needs_initialization && !new_plugin->initialize(container)) {
     // We couldn't initialize the new plugin. Restore the old one and abort.
     container->setPlugin(plugin());
     return;
   }
 
   // The plugin has been removed from the page. Destroy the old plugin. We
   // will be destroyed as soon as V8 garbage collects us.
   if (!element.pluginContainer()) {
     plugin()->destroy();
     return;
   }
 
   // During initialization, the new plugin might have replaced itself in turn
   // with another plugin. Make sure not to use the passed in |new_plugin| after
   // this point.
   new_plugin = container->plugin();
 
   plugin()->RestoreTitleText();
   container->invalidate();
   container->reportGeometry();
   plugin()->ReplayReceivedData(new_plugin);
   plugin()->destroy();
 }
 
-void LoadablePluginPlaceholder::HidePlugin() {
-  hidden_ = true;
-  if (!plugin())
-    return;
-  WebPluginContainer* container = plugin()->container();
-  WebElement element = container->element();
-  element.setAttribute("style", "display: none;");
-  // If we have a width and height, search for a parent (often <div>) with the
-  // same dimensions. If we find such a parent, hide that as well.
-  // This makes much more uncovered page content usable (including clickable)
-  // as opposed to merely visible.
-  // TODO(cevans) -- it's a foul heuristic but we're going to tolerate it for
-  // now for these reasons:
-  // 1) Makes the user experience better.
-  // 2) Foulness is encapsulated within this single function.
-  // 3) Confidence in no fasle positives.
-  // 4) Seems to have a good / low false negative rate at this time.
-  if (element.hasAttribute("width") && element.hasAttribute("height")) {
-    std::string width_str("width:[\\s]*");
-    width_str += element.getAttribute("width").utf8().data();
-    if (EndsWith(width_str, "px", false)) {
-      width_str = width_str.substr(0, width_str.length() - 2);
-    }
-    base::TrimWhitespace(width_str, base::TRIM_TRAILING, &width_str);
-    width_str += "[\\s]*px";
-    std::string height_str("height:[\\s]*");
-    height_str += element.getAttribute("height").utf8().data();
-    if (EndsWith(height_str, "px", false)) {
-      height_str = height_str.substr(0, height_str.length() - 2);
-    }
-    base::TrimWhitespace(height_str, base::TRIM_TRAILING, &height_str);
-    height_str += "[\\s]*px";
-    WebNode parent = element;
-    while (!parent.parentNode().isNull()) {
-      parent = parent.parentNode();
-      if (!parent.isElementNode())
-        continue;
-      element = parent.toConst<WebElement>();
-      if (element.hasAttribute("style")) {
-        std::string style_str = element.getAttribute("style").utf8();
-        if (RE2::PartialMatch(style_str, width_str) &&
-            RE2::PartialMatch(style_str, height_str))
-          element.setAttribute("style", "display: none;");
-      }
-    }
-  }
-}
-
 void LoadablePluginPlaceholder::SetMessage(const base::string16& message) {
   message_ = message;
   if (finished_loading_)
     UpdateMessage();
 }
 
 void LoadablePluginPlaceholder::UpdateMessage() {
   if (!plugin())
     return;
   std::string script =
       "window.setMessage(" + base::GetQuotedJSONString(message_) + ")";
   plugin()->web_view()->mainFrame()->executeScript(
-      WebScriptSource(base::UTF8ToUTF16(script)));
+      blink::WebScriptSource(base::UTF8ToUTF16(script)));
 }
 
 void LoadablePluginPlaceholder::PluginDestroyed() {
-#if defined(ENABLE_PLUGINS)
   if (power_saver_enabled_) {
     if (premade_throttler_) {
       // Since the premade plugin has been detached from the container, it will
       // not be automatically destroyed along with the page.
       premade_throttler_->GetWebPlugin()->destroy();
       premade_throttler_ = nullptr;
     } else if (is_blocked_for_power_saver_poster_) {
       // Record the NEVER unthrottle count only if there is no throttler.
       PluginInstanceThrottler::RecordUnthrottleMethodMetric(
           PluginInstanceThrottler::UNTHROTTLE_METHOD_NEVER);
     }
 
     // Prevent processing subsequent calls to MarkPluginEssential.
     power_saver_enabled_ = false;
   }
-#endif
 
   PluginPlaceholder::PluginDestroyed();
 }
 
 v8::Local<v8::Object> LoadablePluginPlaceholder::GetV8ScriptableObject(
     v8::Isolate* isolate) const {
-#if defined(ENABLE_PLUGINS)
   // Pass through JavaScript access to the underlying throttled plugin.
   if (premade_throttler_ && premade_throttler_->GetWebPlugin()) {
     return premade_throttler_->GetWebPlugin()->v8ScriptableObject(isolate);
   }
-#endif
   return v8::Local<v8::Object>();
 }
 
 void LoadablePluginPlaceholder::WasShown() {
   if (is_blocked_for_background_tab_) {
     is_blocked_for_background_tab_ = false;
     if (!LoadingBlocked())
       LoadPlugin();
   }
 }
@@ skipping 14 matching lines @@
   if (is_blocked_for_prerendering_) {
     is_blocked_for_prerendering_ = false;
     if (!LoadingBlocked())
       LoadPlugin();
   }
 }
 
 void LoadablePluginPlaceholder::LoadPlugin() {
   // This is not strictly necessary but is an important defense in case the
   // event propagation changes between "close" vs. "click-to-play".
-  if (hidden_)
+  if (hidden())
     return;
   if (!plugin())
     return;
   if (!allow_loading_) {
     NOTREACHED();
     return;
   }
 
   if (premade_throttler_) {
     premade_throttler_->SetHiddenForPlaceholder(false /* hidden */);
     ReplacePlugin(premade_throttler_->GetWebPlugin());
     premade_throttler_ = nullptr;
   } else {
     ReplacePlugin(CreatePlugin());
   }
 }
 
 void LoadablePluginPlaceholder::LoadCallback() {
   RenderThread::Get()->RecordAction(UserMetricsAction("Plugin_Load_Click"));
-#if defined(ENABLE_PLUGINS)
   // If the user specifically clicks on the plugin content's placeholder,
   // disable power saver throttling for this instance.
   MarkPluginEssential(PluginInstanceThrottler::UNTHROTTLE_METHOD_BY_CLICK);
-#endif
   LoadPlugin();
 }
 
-void LoadablePluginPlaceholder::HideCallback() {
-  RenderThread::Get()->RecordAction(UserMetricsAction("Plugin_Hide_Click"));
-  HidePlugin();
-}
-
 void LoadablePluginPlaceholder::DidFinishLoadingCallback() {
   finished_loading_ = true;
   if (message_.length() > 0)
     UpdateMessage();
 
   // Wait for the placeholder to finish loading to hide the premade plugin.
   // This is necessary to prevent a flicker.
   if (premade_throttler_ && power_saver_enabled_)
     premade_throttler_->SetHiddenForPlaceholder(true /* hidden */);
 
   // Set an attribute and post an event, so browser tests can wait for the
   // placeholder to be ready to receive simulated user input.
   if (base::CommandLine::ForCurrentProcess()->HasSwitch(
           switches::kEnablePluginPlaceholderTesting)) {
-    WebElement element = plugin()->container()->element();
+    blink::WebElement element = plugin()->container()->element();
     element.setAttribute("placeholderLoaded", "true");
 
     scoped_ptr<content::V8ValueConverter> converter(
         content::V8ValueConverter::create());
     base::StringValue value("placeholderLoaded");
     blink::WebSerializedScriptValue message_data =
         blink::WebSerializedScriptValue::serialize(converter->ToV8Value(
             &value, element.document().frame()->mainWorldScriptContext()));
 
     blink::WebDOMEvent event = element.document().createEvent("MessageEvent");
@@ skipping 26 matching lines @@
   return identifier_;
 }
 
 bool LoadablePluginPlaceholder::LoadingBlocked() const {
   DCHECK(allow_loading_);
   return is_blocked_for_background_tab_ || is_blocked_for_power_saver_poster_ ||
          is_blocked_for_prerendering_;
 }
 
 }  // namespace plugins