[tracing] Support BACKGROUND mode in MemoryCache dump provider

third_party/WebKit/Source/core/fetch/ImageResource.cpp

Index: third_party/WebKit/Source/core/fetch/ImageResource.cpp
diff --git a/third_party/WebKit/Source/core/fetch/ImageResource.cpp b/third_party/WebKit/Source/core/fetch/ImageResource.cpp
index 9a98251a0e375223dae14098aef57c85805722a0..195ff90d5d29aedd7bd7413232b6fb5d13cabcf6 100644
--- a/third_party/WebKit/Source/core/fetch/ImageResource.cpp
+++ b/third_party/WebKit/Source/core/fetch/ImageResource.cpp
@@ -432,6 +432,14 @@ void ImageResource::finish(double loadFinishTime)
     Resource::finish(loadFinishTime);
 }
 
+void ImageResource::onMemoryDump(WebMemoryDumpLevelOfDetail levelOfDetail, WebProcessMemoryDump* memoryDump) const
+{
+    Resource::onMemoryDump(levelOfDetail, memoryDump);
+    const String name = getMemoryDumpName() + "/encoded_data";
+    if (m_image && !m_image->isNull())
+        m_image->data()->onMemoryDump(name, memoryDump);
+}
+
 void ImageResource::error(const ResourceError& error)
 {
     if (m_multipartParser)