Remove most ScopedVector usage from c/b/extensions.

chrome/browser/extensions/api/tab_capture/offscreen_tab.cc

Index: chrome/browser/extensions/api/tab_capture/offscreen_tab.cc
diff --git a/chrome/browser/extensions/api/tab_capture/offscreen_tab.cc b/chrome/browser/extensions/api/tab_capture/offscreen_tab.cc
index d7e26772b4f17f67bb2c13209f3559be533ac4f9..f50fdf9c3cb89cd7087e96e447cd697affb933df 100644
--- a/chrome/browser/extensions/api/tab_capture/offscreen_tab.cc
+++ b/chrome/browser/extensions/api/tab_capture/offscreen_tab.cc
@@ -8,6 +8,7 @@
 
 #include "base/bind.h"
 #include "base/macros.h"
+#include "base/memory/ptr_util.h"
 #include "chrome/browser/extensions/api/tab_capture/tab_capture_registry.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/web_contents_sizer.h"
@@ -57,15 +58,24 @@ OffscreenTab* OffscreenTabsOwner::OpenNewTab(
   if (tabs_.size() >= kMaxOffscreenTabsPerExtension)
     return nullptr;  // Maximum number of offscreen tabs reached.
 
-  tabs_.push_back(new OffscreenTab(this));
+  // OffscreenTab cannot be created with MakeUnique<OffscreenTab> since the
+  // constructor is protected. So create it separately, and then move it to
+  // |tabs_| below.
+  std::unique_ptr<OffscreenTab> offscreen_tab(new OffscreenTab(this));
+  tabs_.push_back(std::move(offscreen_tab));
   tabs_.back()->Start(start_url, initial_size, optional_presentation_id);
-  return tabs_.back();
+  return tabs_.back().get();
 }
 
 void OffscreenTabsOwner::DestroyTab(OffscreenTab* tab) {
-  const auto it = std::find(tabs_.begin(), tabs_.end(), tab);
-  if (it != tabs_.end())
-    tabs_.erase(it);
+  for (std::vector<std::unique_ptr<OffscreenTab>>::iterator iter =
+           tabs_.begin();
+       iter != tabs_.end(); ++iter) {
+    if (iter->get() == tab) {
+      tabs_.erase(iter);
+      break;
+    }
+  }
 }
 
 OffscreenTab::OffscreenTab(OffscreenTabsOwner* owner)