[win] Create ModuleDatabase and ModuleEventSinkImpl.

chrome/browser/conflicts/module_database_win_unittest.cc

Index: chrome/browser/conflicts/module_database_win_unittest.cc
diff --git a/chrome/browser/conflicts/module_database_win_unittest.cc b/chrome/browser/conflicts/module_database_win_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..4990ea4d836d1625b05219f710768e86cc84264f
--- /dev/null
+++ b/chrome/browser/conflicts/module_database_win_unittest.cc
@@ -0,0 +1,551 @@
+// Copyright 2016 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 "chrome/browser/conflicts/module_database_win.h"
+
+#include <algorithm>
+
+#include "base/bind.h"
+#include "base/message_loop/message_loop.h"
+#include "base/run_loop.h"
+#include "base/strings/utf_string_conversions.h"
+#include "base/threading/simple_thread.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace {
+
+// A simple mechanism for running a single task on a separate thread.
+class SingleTaskRunner : public base::SimpleThread {
+ public:
+  explicit SingleTaskRunner(const base::Closure& task)
+      : base::SimpleThread("SingleTaskRunner"), task_(task) {}
+
+  // Runs the provided task and exits.
+  void Run() override { task_.Run(); }
+
+ private:
+  base::Closure task_;
+  DISALLOW_COPY_AND_ASSIGN(SingleTaskRunner);
+};
+
+// Launches a thread and runs a single task on it.
+void RunTask(const base::Closure& task) {
+  SingleTaskRunner task_runner(task);
+  task_runner.Start();
+  task_runner.Join();
+}
+
+const uint32_t kPid1 = 1234u;
+const uint32_t kPid2 = 2345u;
+
+const wchar_t kDll1[] = L"dummy.dll";
+const wchar_t kDll2[] = L"foo.dll";
+
+const size_t kSize1 = 100 * 4096;
+const size_t kSize2 = 20 * 4096;
+
+void* kGoodAddress1 = reinterpret_cast<void*>(0x04000000u);
+void* kGoodAddress2 = reinterpret_cast<void*>(0x05000000u);
+
+}  // namespace
+
+class TestModuleDatabase : ModuleDatabase {
+ public:
+  // Types.
+  using ModuleDatabase::ModuleId;
+  using ModuleDatabase::ModuleLoadAddresses;
+
+  // Constants.
+  using ModuleDatabase::kInvalidIndex;
+
+  // Functions.
+  using ModuleDatabase::FindLoadAddressIndexById;
+  using ModuleDatabase::FindLoadAddressIndexByAddress;
+  using ModuleDatabase::InsertLoadAddress;
+  using ModuleDatabase::RemoveLoadAddressById;
+  using ModuleDatabase::RemoveLoadAddressByIndex;
+};
+
+class ModuleDatabaseTest : public testing::Test {
+ protected:
+  ModuleDatabaseTest()
+      : dll1_(kDll1),
+        dll2_(kDll2),
+        message_loop_(new base::MessageLoop),

[grt (UTC plus 2), 2016/12/20 11:11:34]

MakeUnique?

[chrisha, 2016/12/20 19:46:24]

How is that any shorter or better? I can see that argument when doing
assignment, as it avoid using "reset" and "new", but it actually makes things
longer and less clear, IMO, in the constructor.

[grt (UTC plus 2), 2016/12/20 21:09:53]

With naked "new", I have to check the type of |message_loop_| to be sure it's a
smart pointer. With MakeUnique, I know it must be.

[chrisha, 2016/12/21 20:14:59]

Okay, fair enough. Done.

+        module_database_(new ModuleDatabase(message_loop_->task_runner())) {}
+
+  void RunLoopUntilIdle() {
+    base::RunLoop run_loop;

[grt (UTC plus 2), 2016/12/20 11:11:34]

nit:
    base::RunLoop().RunUntilIdle();

[chrisha, 2016/12/20 19:46:24]

Done.

+    run_loop.RunUntilIdle();
+  }
+
+  const ModuleDatabase::ModuleSet& modules() {
+    return module_database_->modules_;
+  }
+
+  const ModuleDatabase::ProcessSet& processes() {
+    return module_database_->processes_;
+  }
+
+  static uint32_t ProcessTypeToBit(content::ProcessType process_type) {
+    return ModuleDatabase::ProcessTypeToBit(process_type);
+  }
+
+  // Counts the occurrences of the given |module_id| in the given collection of
+  // |load_addresses|.
+  static size_t ModuleIdCount(
+      ModuleDatabase::ModuleId module_id,
+      const ModuleDatabase::ModuleLoadAddresses& load_addresses) {
+    size_t count = 0;
+    for (const auto& load_address : load_addresses) {
+      if (load_address.first == module_id)
+        ++count;
+    }
+    return count;
+  }
+
+ protected:
+  const base::FilePath dll1_;
+  const base::FilePath dll2_;
+
+  std::unique_ptr<base::MessageLoop> message_loop_;
+  std::unique_ptr<ModuleDatabase> module_database_;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(ModuleDatabaseTest);
+};
+
+TEST_F(ModuleDatabaseTest, LoadAddressVectorOperations) {
+  using TMD = TestModuleDatabase;
+  TestModuleDatabase::ModuleLoadAddresses la;
+
+  // Finds should fail in an empty collection.
+  EXPECT_EQ(TMD::kInvalidIndex, TMD::FindLoadAddressIndexById(0, la));
+  EXPECT_EQ(TMD::kInvalidIndex, TMD::FindLoadAddressIndexById(0x04000000, la));
+
+  // A first insert should work. Don't start with ModuleId 0 so that later
+  // inserts can insert that module.
+  TMD::InsertLoadAddress(10, 0x04000000, &la);
+  EXPECT_EQ(1u, la.size());
+  EXPECT_EQ(10, la[0].first);
+  EXPECT_EQ(0x04000000u, la[0].second);
+
+  // Finds should work.
+  EXPECT_EQ(TMD::kInvalidIndex, TMD::FindLoadAddressIndexById(0, la));
+  EXPECT_EQ(TMD::kInvalidIndex, TMD::FindLoadAddressIndexById(0x03000000, la));
+  EXPECT_EQ(0, TMD::FindLoadAddressIndexById(10, la));
+  EXPECT_EQ(0, TMD::FindLoadAddressIndexByAddress(0x04000000, la));
+
+  // A second insert should work. This is the new max so should be at the end
+  // of the collection.
+  TMD::InsertLoadAddress(12, 0x06000000, &la);
+  EXPECT_EQ(2u, la.size());
+  EXPECT_EQ(10, la[0].first);
+  EXPECT_EQ(0x04000000u, la[0].second);
+  EXPECT_EQ(12, la[1].first);
+  EXPECT_EQ(0x06000000u, la[1].second);
+
+  // Finds should work.
+  EXPECT_EQ(TMD::kInvalidIndex, TMD::FindLoadAddressIndexById(0, la));
+  EXPECT_EQ(TMD::kInvalidIndex, TMD::FindLoadAddressIndexById(0x03000000, la));
+  EXPECT_EQ(0, TMD::FindLoadAddressIndexById(10, la));
+  EXPECT_EQ(0, TMD::FindLoadAddressIndexByAddress(0x04000000, la));
+  EXPECT_EQ(1, TMD::FindLoadAddressIndexById(12, la));
+  EXPECT_EQ(1, TMD::FindLoadAddressIndexByAddress(0x06000000, la));
+
+  // Another insert should work. This is not the new max, so a swap should
+  // happen to keep the maximum element at the end of the collection.
+  TMD::InsertLoadAddress(11, 0x05000000, &la);
+  EXPECT_EQ(3u, la.size());
+  EXPECT_EQ(10, la[0].first);
+  EXPECT_EQ(0x04000000u, la[0].second);
+  EXPECT_EQ(11, la[1].first);
+  EXPECT_EQ(0x05000000u, la[1].second);
+  EXPECT_EQ(12, la[2].first);
+  EXPECT_EQ(0x06000000u, la[2].second);
+
+  // An insert of an existing module should work, but simply overwrite the
+  // load address.
+  TMD::InsertLoadAddress(11, 0x0F000000, &la);
+  EXPECT_EQ(3u, la.size());
+  EXPECT_EQ(11, la[1].first);
+  EXPECT_EQ(0x0F000000u, la[1].second);
+  TMD::InsertLoadAddress(11, 0x05000000, &la);
+  EXPECT_EQ(3u, la.size());
+  EXPECT_EQ(11, la[1].first);
+  EXPECT_EQ(0x05000000u, la[1].second);
+
+  // Finds should work.
+  EXPECT_EQ(TMD::kInvalidIndex, TMD::FindLoadAddressIndexById(0, la));
+  EXPECT_EQ(TMD::kInvalidIndex, TMD::FindLoadAddressIndexById(0x03000000, la));
+  EXPECT_EQ(0, TMD::FindLoadAddressIndexById(10, la));
+  EXPECT_EQ(0, TMD::FindLoadAddressIndexByAddress(0x04000000, la));
+  EXPECT_EQ(1, TMD::FindLoadAddressIndexById(11, la));
+  EXPECT_EQ(1, TMD::FindLoadAddressIndexByAddress(0x05000000, la));
+  EXPECT_EQ(2, TMD::FindLoadAddressIndexById(12, la));
+  EXPECT_EQ(2, TMD::FindLoadAddressIndexByAddress(0x06000000, la));
+
+  // Do some inserts of lower modules IDs. This ensures that we'll have some
+  // higher module IDs in the vector before some lower modules IDs, for testing
+  // the deletion logic.
+  TMD::InsertLoadAddress(3, 0x07000000, &la);
+  TMD::InsertLoadAddress(4, 0x08000000, &la);
+  TMD::InsertLoadAddress(5, 0x09000000, &la);
+  EXPECT_EQ(6u, la.size());
+  EXPECT_EQ(10, la[0].first);
+  EXPECT_EQ(0x04000000u, la[0].second);
+  EXPECT_EQ(11, la[1].first);
+  EXPECT_EQ(0x05000000u, la[1].second);
+  EXPECT_EQ(3, la[2].first);
+  EXPECT_EQ(0x07000000u, la[2].second);
+  EXPECT_EQ(4, la[3].first);
+  EXPECT_EQ(0x08000000u, la[3].second);
+  EXPECT_EQ(5, la[4].first);
+  EXPECT_EQ(0x09000000u, la[4].second);
+  EXPECT_EQ(12, la[5].first);
+  EXPECT_EQ(0x06000000u, la[5].second);
+
+  // Remove an element that isn't in the second last position. The second last
+  // element should be swapped into its position, and the last element moved
+  // to the second last place.
+  TMD::RemoveLoadAddressByIndex(2, &la);
+  EXPECT_EQ(5u, la.size());
+  EXPECT_EQ(10, la[0].first);
+  EXPECT_EQ(0x04000000u, la[0].second);
+  EXPECT_EQ(11, la[1].first);
+  EXPECT_EQ(0x05000000u, la[1].second);
+  EXPECT_EQ(5, la[2].first);
+  EXPECT_EQ(0x09000000u, la[2].second);
+  EXPECT_EQ(4, la[3].first);
+  EXPECT_EQ(0x08000000u, la[3].second);
+  EXPECT_EQ(12, la[4].first);
+  EXPECT_EQ(0x06000000u, la[4].second);
+
+  // Remove the second last element. Only the last element should move.
+  TMD::RemoveLoadAddressByIndex(3, &la);
+  EXPECT_EQ(4u, la.size());
+  EXPECT_EQ(10, la[0].first);
+  EXPECT_EQ(0x04000000u, la[0].second);
+  EXPECT_EQ(11, la[1].first);
+  EXPECT_EQ(0x05000000u, la[1].second);
+  EXPECT_EQ(5, la[2].first);
+  EXPECT_EQ(0x09000000u, la[2].second);
+  EXPECT_EQ(12, la[3].first);
+  EXPECT_EQ(0x06000000u, la[3].second);
+
+  // Remove the last element. The new maximum should be found moved to the
+  // end.
+  TMD::RemoveLoadAddressByIndex(3, &la);
+  EXPECT_EQ(3u, la.size());
+  EXPECT_EQ(10, la[0].first);
+  EXPECT_EQ(0x04000000u, la[0].second);
+  EXPECT_EQ(5, la[1].first);
+  EXPECT_EQ(0x09000000u, la[1].second);
+  EXPECT_EQ(11, la[2].first);
+  EXPECT_EQ(0x05000000u, la[2].second);
+
+  // Remove the last element by ModuleId. The remaining modules should be
+  // swapped.
+  TMD::RemoveLoadAddressById(11, &la);
+  EXPECT_EQ(2u, la.size());
+  EXPECT_EQ(5, la[0].first);
+  EXPECT_EQ(0x09000000u, la[0].second);
+  EXPECT_EQ(10, la[1].first);
+  EXPECT_EQ(0x04000000u, la[1].second);
+
+  // Remove the first element by ModuleId.
+  TMD::RemoveLoadAddressById(5, &la);
+  EXPECT_EQ(1u, la.size());
+  EXPECT_EQ(10, la[0].first);
+  EXPECT_EQ(0x04000000u, la[0].second);
+
+  // Remove the only remaining element.
+  TMD::RemoveLoadAddressByIndex(0, &la);
+  EXPECT_TRUE(la.empty());
+}
+
+TEST_F(ModuleDatabaseTest, LoadAddressVectorStressTest) {
+  using TMD = TestModuleDatabase;
+  TestModuleDatabase::ModuleLoadAddresses la;
+
+  for (size_t n = 1; n < 200; ++n) {
+    // Will keep track of which elements have been inserted.
+    std::vector<bool> inserted(n);
+    size_t inserted_count = 0;
+
+    // Generate a shuffled list of IDs. This will be the insertion order.
+    // More insertions than elements will occur so that rewrites occur.,
+    std::vector<TMD::ModuleId> ids(11 * n / 10);
+    for (size_t i = 0; i < 11 * n / 10; ++i)
+      ids[i] = i % n;
+    std::random_shuffle(ids.begin(), ids.end());
+
+    // Do the insertions.
+    for (auto id : ids) {
+      if (!inserted[id]) {
+        inserted[id] = true;
+        ++inserted_count;
+      }
+
+      // Generate a load address. The load address bakes in the index so that
+      // searching by load address is easy.
+      uintptr_t load_address = static_cast<uintptr_t>(id) << 16;
+
+      // Do the insertion.
+      TMD::InsertLoadAddress(id, load_address, &la);
+      EXPECT_EQ(inserted_count, la.size());
+    }
+
+    // Validate that every element is there, via both search mechanisms.
+    for (size_t id = 0; id < n; ++id) {
+      uintptr_t load_address = static_cast<uintptr_t>(id) << 16;
+      int index1 = TMD::FindLoadAddressIndexById(id, la);
+      int index2 = TMD::FindLoadAddressIndexByAddress(load_address, la);
+      EXPECT_NE(TMD::kInvalidIndex, index1);
+      EXPECT_EQ(index1, index2);
+    }
+
+    // Generate the deletion order.
+    ids.resize(n);
+    for (size_t i = 0; i < ids.size(); ++i)
+      ids[i] = i;
+    std::random_shuffle(ids.begin(), ids.end());
+
+    // Do the deletions.
+    for (auto id : ids) {
+      --inserted_count;
+      TMD::RemoveLoadAddressById(id, &la);
+      EXPECT_EQ(inserted_count, la.size());
+    }
+  }
+}
+
+TEST_F(ModuleDatabaseTest, TasksAreBounced) {
+  // Run a task on the current thread. This should not be bounced, so no
+  // task should be scheduled on the task runner.
+  module_database_->OnProcessStarted(kPid1, content::PROCESS_TYPE_BROWSER);
+  EXPECT_TRUE(message_loop_->IsIdleForTesting());
+  module_database_->OnModuleEvent(
+      kPid1, ModuleWatcher::ModuleEvent(mojom::ModuleEventType::MODULE_LOADED,
+                                        dll1_, kGoodAddress1, kSize1));
+  EXPECT_TRUE(message_loop_->IsIdleForTesting());
+  module_database_->OnProcessEnded(kPid1);
+  EXPECT_TRUE(message_loop_->IsIdleForTesting());
+
+  // Indicate another process start on this thread. This call can't be
+  // bounced.
+  module_database_->OnProcessStarted(kPid2, content::PROCESS_TYPE_BROWSER);
+
+  // Run similar tasks on another thread. These should be bounced.
+  RunTask(base::Bind(
+      &ModuleDatabase::OnModuleEvent, base::Unretained(module_database_.get()),
+      kPid2, ModuleWatcher::ModuleEvent(mojom::ModuleEventType::MODULE_LOADED,
+                                        dll1_, kGoodAddress1, kSize1)));
+  EXPECT_FALSE(message_loop_->IsIdleForTesting());
+  RunLoopUntilIdle();
+
+  RunTask(base::Bind(&ModuleDatabase::OnProcessEnded,
+                     base::Unretained(module_database_.get()), kPid2));
+  EXPECT_FALSE(message_loop_->IsIdleForTesting());
+  RunLoopUntilIdle();
+}
+
+TEST_F(ModuleDatabaseTest, EventsWithoutProcessIgnore) {
+  EXPECT_EQ(0u, modules().size());
+  EXPECT_EQ(0u, processes().size());
+
+  module_database_->OnModuleEvent(
+      kPid1,
+      ModuleWatcher::ModuleEvent(mojom::ModuleEventType::MODULE_ALREADY_LOADED,
+                                 dll1_, kGoodAddress1, kSize1));
+
+  EXPECT_EQ(0u, modules().size());
+  EXPECT_EQ(0u, processes().size());
+}
+
+TEST_F(ModuleDatabaseTest, OutOfOrderEventsHandled) {
+  EXPECT_EQ(0u, modules().size());
+  EXPECT_EQ(0u, processes().size());
+
+  // Start a process.
+  module_database_->OnProcessStarted(kPid1, content::PROCESS_TYPE_BROWSER);
+  EXPECT_EQ(0u, modules().size());
+  EXPECT_EQ(1u, processes().size());
+  auto p1 = processes().begin();
+  EXPECT_EQ(kPid1, p1->process_id);
+  EXPECT_EQ(content::PROCESS_TYPE_BROWSER, p1->process_type);
+  EXPECT_EQ(0u, p1->loaded_modules.size());
+  EXPECT_EQ(0u, p1->unloaded_modules.size());
+
+  // Indicate a module unload. This should create an unloaded module entry.
+  module_database_->OnModuleEvent(
+      kPid1, ModuleWatcher::ModuleEvent(mojom::ModuleEventType::MODULE_UNLOADED,
+                                        dll1_, kGoodAddress1, kSize1));
+  EXPECT_EQ(1u, modules().size());
+  EXPECT_EQ(1u, processes().size());
+  EXPECT_EQ(0u, p1->loaded_modules.size());
+  EXPECT_EQ(1u, p1->unloaded_modules.size());
+
+  // Now do a corresponding load. This should create a loaded module entry and
+  // erase the unloaded module entry.
+  module_database_->OnModuleEvent(
+      kPid1, ModuleWatcher::ModuleEvent(mojom::ModuleEventType::MODULE_LOADED,
+                                        dll1_, kGoodAddress1, kSize1));
+  EXPECT_EQ(1u, modules().size());
+  EXPECT_EQ(1u, processes().size());
+  EXPECT_EQ(1u, p1->loaded_modules.size());
+  EXPECT_EQ(0u, p1->unloaded_modules.size());
+}
+
+TEST_F(ModuleDatabaseTest, OutOfOrderUnloadIgnored) {
+  EXPECT_EQ(0u, modules().size());
+  EXPECT_EQ(0u, processes().size());
+
+  // Start a process.
+  module_database_->OnProcessStarted(kPid1, content::PROCESS_TYPE_BROWSER);
+  EXPECT_EQ(0u, modules().size());
+  EXPECT_EQ(1u, processes().size());
+  auto p1 = processes().begin();
+  EXPECT_EQ(kPid1, p1->process_id);
+  EXPECT_EQ(content::PROCESS_TYPE_BROWSER, p1->process_type);
+  EXPECT_EQ(0u, p1->loaded_modules.size());
+  EXPECT_EQ(0u, p1->unloaded_modules.size());
+
+  // Indicate a module unload using the alternative API for calls via IPC. This
+  // should do nothing.
+  module_database_->OnModuleEvent(
+      kPid1, ModuleWatcher::ModuleEvent(mojom::ModuleEventType::MODULE_UNLOADED,
+                                        dll1_, kGoodAddress1, kSize1));
+  EXPECT_EQ(1u, modules().size());
+  EXPECT_EQ(1u, processes().size());
+  EXPECT_EQ(0u, p1->loaded_modules.size());
+  EXPECT_EQ(1u, p1->unloaded_modules.size());
+}
+
+TEST_F(ModuleDatabaseTest, DatabaseIsConsistent) {
+  EXPECT_EQ(0u, modules().size());
+  EXPECT_EQ(0u, processes().size());
+
+  // Start a process.
+  module_database_->OnProcessStarted(kPid1, content::PROCESS_TYPE_BROWSER);
+  EXPECT_EQ(0u, modules().size());
+  EXPECT_EQ(1u, processes().size());
+  auto p1 = processes().begin();
+  EXPECT_EQ(kPid1, p1->process_id);
+  EXPECT_EQ(content::PROCESS_TYPE_BROWSER, p1->process_type);
+  EXPECT_EQ(0u, p1->loaded_modules.size());
+  EXPECT_EQ(0u, p1->unloaded_modules.size());
+
+  // Indicate an already loaded module.
+  module_database_->OnModuleEvent(
+      kPid1,
+      ModuleWatcher::ModuleEvent(mojom::ModuleEventType::MODULE_ALREADY_LOADED,
+                                 dll1_, kGoodAddress1, kSize1));
+  EXPECT_EQ(1u, modules().size());
+  EXPECT_EQ(1u, processes().size());
+
+  // Ensure that the process and module sets are up to date.
+  auto m1 = modules().begin();
+  EXPECT_EQ(dll1_, m1->module_path);
+  EXPECT_EQ(ProcessTypeToBit(content::PROCESS_TYPE_BROWSER), m1->process_types);
+  EXPECT_EQ(kPid1, p1->process_id);
+  EXPECT_EQ(content::PROCESS_TYPE_BROWSER, p1->process_type);
+  EXPECT_EQ(1u, p1->loaded_modules.size());
+  EXPECT_EQ(0u, p1->unloaded_modules.size());
+  EXPECT_EQ(1u, ModuleIdCount(m1->module_id, p1->loaded_modules));
+
+  // Provide a redundant load message for that module.
+  module_database_->OnModuleEvent(
+      kPid1, ModuleWatcher::ModuleEvent(mojom::ModuleEventType::MODULE_LOADED,
+                                        dll1_, kGoodAddress1, kSize1));
+  EXPECT_EQ(1u, modules().size());
+  EXPECT_EQ(1u, processes().size());
+
+  // Ensure that the process and module sets haven't changed.
+  EXPECT_EQ(dll1_, m1->module_path);
+  EXPECT_EQ(ProcessTypeToBit(content::PROCESS_TYPE_BROWSER), m1->process_types);
+  EXPECT_EQ(kPid1, p1->process_id);
+  EXPECT_EQ(content::PROCESS_TYPE_BROWSER, p1->process_type);
+  EXPECT_EQ(1u, p1->loaded_modules.size());
+  EXPECT_EQ(0u, p1->unloaded_modules.size());
+  EXPECT_EQ(1u, ModuleIdCount(m1->module_id, p1->loaded_modules));
+
+  // Load a second module into the process.
+  module_database_->OnModuleEvent(
+      kPid1, ModuleWatcher::ModuleEvent(mojom::ModuleEventType::MODULE_LOADED,
+                                        dll2_, kGoodAddress2, kSize2));
+  EXPECT_EQ(2u, modules().size());
+  EXPECT_EQ(1u, processes().size());
+
+  // Ensure that the process and module sets are up to date.
+  auto m2 = modules().rbegin();
+  EXPECT_EQ(dll2_, m2->module_path);
+  EXPECT_EQ(ProcessTypeToBit(content::PROCESS_TYPE_BROWSER), m2->process_types);
+  EXPECT_EQ(kPid1, p1->process_id);
+  EXPECT_EQ(content::PROCESS_TYPE_BROWSER, p1->process_type);
+  EXPECT_EQ(2u, p1->loaded_modules.size());
+  EXPECT_EQ(0u, p1->unloaded_modules.size());
+  EXPECT_EQ(1u, ModuleIdCount(m1->module_id, p1->loaded_modules));
+  EXPECT_EQ(1u, ModuleIdCount(m2->module_id, p1->loaded_modules));
+
+  // Unload the second module.
+  module_database_->OnModuleEvent(
+      kPid1, ModuleWatcher::ModuleEvent(mojom::ModuleEventType::MODULE_UNLOADED,
+                                        dll2_, kGoodAddress2, kSize2));
+  EXPECT_EQ(2u, modules().size());
+  EXPECT_EQ(1u, processes().size());
+
+  // Ensure that the process and module sets are up to date.
+  EXPECT_EQ(dll2_, m2->module_path);
+  EXPECT_EQ(ProcessTypeToBit(content::PROCESS_TYPE_BROWSER), m2->process_types);
+  EXPECT_EQ(kPid1, p1->process_id);
+  EXPECT_EQ(content::PROCESS_TYPE_BROWSER, p1->process_type);
+  EXPECT_EQ(1u, p1->loaded_modules.size());
+  EXPECT_EQ(1u, p1->unloaded_modules.size());
+  EXPECT_EQ(1u, ModuleIdCount(m1->module_id, p1->loaded_modules));
+  EXPECT_EQ(1u, ModuleIdCount(m2->module_id, p1->unloaded_modules));
+
+  // Start a process.
+  module_database_->OnProcessStarted(kPid2, content::PROCESS_TYPE_RENDERER);
+  EXPECT_EQ(2u, modules().size());
+  EXPECT_EQ(2u, processes().size());
+  auto p2 = processes().rbegin();
+  EXPECT_EQ(kPid2, p2->process_id);
+  EXPECT_EQ(content::PROCESS_TYPE_RENDERER, p2->process_type);
+  EXPECT_EQ(0u, p2->loaded_modules.size());
+  EXPECT_EQ(0u, p2->unloaded_modules.size());
+
+  // Load the dummy.dll in the second process as well.
+  module_database_->OnModuleEvent(
+      kPid2,
+      ModuleWatcher::ModuleEvent(mojom::ModuleEventType::MODULE_ALREADY_LOADED,
+                                 dll1_, kGoodAddress1, kSize1));
+  EXPECT_EQ(ProcessTypeToBit(content::PROCESS_TYPE_BROWSER) |
+                ProcessTypeToBit(content::PROCESS_TYPE_RENDERER),
+            m1->process_types);
+  EXPECT_EQ(kPid2, p2->process_id);
+  EXPECT_EQ(content::PROCESS_TYPE_RENDERER, p2->process_type);
+  EXPECT_EQ(1u, p2->loaded_modules.size());
+  EXPECT_EQ(0u, p2->unloaded_modules.size());
+  EXPECT_EQ(1u, ModuleIdCount(m1->module_id, p2->loaded_modules));
+
+  // End the second process without an explicit unload. This invalidates |p2|.
+  module_database_->OnProcessEnded(kPid2);
+  EXPECT_EQ(2u, modules().size());
+  EXPECT_EQ(1u, processes().size());
+  EXPECT_EQ(kPid1, p1->process_id);
+  EXPECT_EQ(ProcessTypeToBit(content::PROCESS_TYPE_BROWSER) |
+                ProcessTypeToBit(content::PROCESS_TYPE_RENDERER),
+            m1->process_types);
+  EXPECT_EQ(ProcessTypeToBit(content::PROCESS_TYPE_BROWSER), m2->process_types);
+
+  // End the first process without an explicit unload. This invalidates |p1|.
+  module_database_->OnProcessEnded(kPid1);
+  EXPECT_EQ(2u, modules().size());
+  EXPECT_EQ(0u, processes().size());
+  EXPECT_EQ(ProcessTypeToBit(content::PROCESS_TYPE_BROWSER) |
+                ProcessTypeToBit(content::PROCESS_TYPE_RENDERER),
+            m1->process_types);
+  EXPECT_EQ(ProcessTypeToBit(content::PROCESS_TYPE_BROWSER), m2->process_types);
+}