Uplift of #5860 (squashed) to beta

browser/android/preferences/background_video_playback_tab_helper.cc

@@ -9,6 +9,7 @@
 
 #include "base/strings/utf_string_conversions.h"
 #include "brave/common/pref_names.h"
+#include "brave/components/brave_shields/browser/brave_shields_util.h"
 #include "chrome/browser/profiles/profile.h"
 #include "components/prefs/pref_service.h"
 #include "content/browser/web_contents/web_contents_impl.h"
@@ -33,16 +34,72 @@ const char k_youtube_background_playback_script[] =
     "    }"
     "}());";
 
+const char k_youtube_ads_block_script[] =
+    "(function() {"
+    "    const prunePaths = ['playerResponse.adPlacements',"
+    "        'playerResponse.playerAds', 'adPlacements', 'playerAds'];"
+    "    const findOwner = function(root, path) {"
+    "        let owner = root;"
+    "        let chain = path;"
+    "        for (;;) {"
+    "            if ( owner instanceof Object === false ) { return; }"
+    "            const pos = chain.indexOf('.');"
+    "            if ( pos === -1 ) {"
+    "                return owner.hasOwnProperty(chain)? [ owner, chain ]:"
+    "                    undefined;"
+    "            }"
+    "            const prop = chain.slice(0, pos);"
+    "            if ( owner.hasOwnProperty(prop) === false ) { return; }"
+    "            owner = owner[prop];"
+    "            chain = chain.slice(pos + 1);"
+    "        }"
+    "    };"
+    "    JSON.parse = new Proxy(JSON.parse, {"
+    "        apply: function() {"
+    "            const r = Reflect.apply(...arguments);"
+    "            for ( const path of prunePaths ) {"
+    "                const details = findOwner(r, path);"
+    "                if ( details !== undefined ) {"
+    "                    delete details[0][details[1]];"
+    "                }"
+    "            }"
+    "            return r;"
+    "        },"
+    "    });"
+    "})();";
+
+bool IsYouTubeDomain(content::WebContents* contents) {
+  if (net::registry_controlled_domains::SameDomainOrHost(
+          contents->GetLastCommittedURL(), GURL("https://www.youtube.com"),
+          net::registry_controlled_domains::INCLUDE_PRIVATE_REGISTRIES)) {
+    return true;
+  }
+
+  return false;
+}
+
 bool IsBackgroundVideoPlaybackEnabled(content::WebContents* contents) {
   PrefService* prefs =
       static_cast<Profile*>(contents->GetBrowserContext())->GetPrefs();
   if (!prefs->GetBoolean(kBackgroundVideoPlaybackEnabled))
     return false;
 
-  if (net::registry_controlled_domains::SameDomainOrHost(
-          contents->GetLastCommittedURL(), GURL("https://www.youtube.com"),
-          net::registry_controlled_domains::INCLUDE_PRIVATE_REGISTRIES)) {
+  content::RenderFrameHost::AllowInjectingJavaScript();
+
+  return true;
+}
+
+bool IsAdBlockEnabled(content::WebContents* contents) {
+  Profile* profile = static_cast<Profile*>(contents->GetBrowserContext());
+
+  brave_shields::ControlType control_type =
+      brave_shields::GetAdControlType(profile,
+      contents->GetLastCommittedURL());
+  if (brave_shields::GetBraveShieldsEnabled(profile,
+        contents->GetLastCommittedURL()) &&
+      control_type != brave_shields::ALLOW) {
     content::RenderFrameHost::AllowInjectingJavaScript();
+
     return true;
   }
 
@@ -61,11 +118,20 @@ BackgroundVideoPlaybackTabHelper::~BackgroundVideoPlaybackTabHelper() {
 
 void BackgroundVideoPlaybackTabHelper::DidFinishNavigation(
     content::NavigationHandle* navigation_handle) {
+  // Filter only YT domains here
+  if (!IsYouTubeDomain(web_contents())) {
+    return;
+  }
   if (IsBackgroundVideoPlaybackEnabled(web_contents())) {
     web_contents()->GetMainFrame()->ExecuteJavaScript(
         base::UTF8ToUTF16(k_youtube_background_playback_script),
         base::NullCallback());
   }
+  if (IsAdBlockEnabled(web_contents())) {
+    web_contents()->GetMainFrame()->ExecuteJavaScript(
+        base::UTF8ToUTF16(k_youtube_ads_block_script),
+        base::NullCallback());
+  }
 }
 
 WEB_CONTENTS_USER_DATA_KEY_IMPL(BackgroundVideoPlaybackTabHelper)