[Experiment] purge-and-suspend

cc/tiles/gpu_image_decode_controller.cc

Index: cc/tiles/gpu_image_decode_controller.cc
diff --git a/cc/tiles/gpu_image_decode_controller.cc b/cc/tiles/gpu_image_decode_controller.cc
index 1c213d52faa49cff619ce8a9c54e347d42260f67..a2db4c110c4ddbfe0e34c3d28f22f5e86375e968 100644
--- a/cc/tiles/gpu_image_decode_controller.cc
+++ b/cc/tiles/gpu_image_decode_controller.cc
@@ -6,6 +6,7 @@
 
 #include <inttypes.h>
 
+#include "base/allocator/allocator_extension.h"
 #include "base/memory/discardable_memory_allocator.h"
 #include "base/memory/ptr_util.h"
 #include "base/metrics/histogram_macros.h"
@@ -358,6 +359,8 @@ GpuImageDecodeController::GpuImageDecodeController(ContextProvider* context,
         this, "cc::GpuImageDecodeController",
         base::ThreadTaskRunnerHandle::Get());
   }
+  memory_pressure_listener_.reset(new base::MemoryPressureListener(base::Bind(
+      &GpuImageDecodeController::OnMemoryPressure, base::Unretained(this))));
 }
 
 GpuImageDecodeController::~GpuImageDecodeController() {
@@ -593,6 +596,12 @@ bool GpuImageDecodeController::OnMemoryDump(
   return true;
 }
 
+void GpuImageDecodeController::OnMemoryPressure(
+    base::MemoryPressureListener::MemoryPressureLevel memory_pressure_level) {
+  SetShouldAggressivelyFreeResources(true);
+  base::allocator::ReleaseFreeMemory();
+}
+
 void GpuImageDecodeController::DecodeImage(const DrawImage& draw_image) {
   base::AutoLock lock(lock_);
   ImageData* image_data = GetImageDataForDrawImage(draw_image);