Add GLES2Implemention::FreeUnusedSharedMemory

gpu/command_buffer/client/mapped_memory_unittest.cc

 // Copyright (c) 2011 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 "gpu/command_buffer/client/mapped_memory.h"
 #include "base/callback.h"
 #include "base/message_loop.h"
 #include "base/mac/scoped_nsautorelease_pool.h"
 #include "base/memory/scoped_ptr.h"
 #include "gpu/command_buffer/client/cmd_buffer_helper.h"
@@ skipping 235 matching lines @@
 // Check if we don't free we don't crash.
 TEST_F(MappedMemoryManagerTest, DontFree) {
   const unsigned int kSize = 1024;
   // Check we can alloc.
   int32 id1 = -1;
   unsigned int offset1 = 0xFFFFFFFFU;
   void* mem1 = manager_->Alloc(kSize, &id1, &offset1);
   ASSERT_TRUE(mem1);
 }
 
+TEST_F(MappedMemoryManagerTest, FreeUnused) {
+  int32 id = -1;
+  unsigned int offset = 0xFFFFFFFFU;
+  void* m1 = manager_->Alloc(kBufferSize, &id, &offset);
+  void* m2 = manager_->Alloc(kBufferSize, &id, &offset);
+  ASSERT_TRUE(m1 != NULL);
+  ASSERT_TRUE(m2 != NULL);
+  EXPECT_EQ(2u, manager_->num_chunks());
+  manager_->FreeUnused();
+  EXPECT_EQ(2u, manager_->num_chunks());
+  manager_->Free(m2);
+  EXPECT_EQ(2u, manager_->num_chunks());
+  manager_->FreeUnused();
+  EXPECT_EQ(1u, manager_->num_chunks());
+  manager_->Free(m1);
+  EXPECT_EQ(1u, manager_->num_chunks());
+  manager_->FreeUnused();
+  EXPECT_EQ(0u, manager_->num_chunks());
+}
+
 }  // namespace gpu