Rewrite vector<T*> into vector<raw_ptr<T, VectorExperimental>>

See chromium-dev announcement:
https://groups.google.com/a/chromium.org/g/chromium-dev/c/sKckMpzHQgY/m/M3SWxEg3AQAJ?utm_medium=email&utm_source=footer

Code review:
- First patch: Automatic rewrite
- Later patches: Manual fixes

The automatic rewrite used the script:
./tools/clang/rewrite_templated_container_fields/rewrite-multiple-platforms.sh

Binary size increase:
The increase is only 33% (+5kB) above the per-patch limit (+16kB). This
is not a lot given the size of the rewrite. Increase of around 500kb was
approved for MiraclePtr.

AX-Relnotes: n/a.
Binary-Size: See commit description.
Bug: 1432993
Change-Id: I8dfc4c2b274b724b99cf408f010da5c821edae9c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5140028
Commit-Queue: Arthur Sonzogni <[email protected]>
Owners-Override: Arthur Sonzogni <[email protected]>
Reviewed-by: Arthur Sonzogni <[email protected]>
Cr-Commit-Position: refs/heads/main@{#1239777}
diff --git a/base/scoped_observation_unittest.cc b/base/scoped_observation_unittest.cc
index ef90b69c..7420418 100644
--- a/base/scoped_observation_unittest.cc
+++ b/base/scoped_observation_unittest.cc
@@ -5,6 +5,7 @@
 #include "base/scoped_observation.h"
 
 #include "base/containers/contains.h"
+#include "base/memory/raw_ptr.h"
 #include "base/ranges/algorithm.h"
 #include "base/scoped_observation_traits.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -26,7 +27,7 @@
   size_t num_observers() const { return observers_.size(); }
 
  private:
-  std::vector<TestSourceObserver*> observers_;
+  std::vector<raw_ptr<TestSourceObserver, VectorExperimental>> observers_;
 };
 
 void TestSource::AddObserver(TestSourceObserver* observer) {