Allow eviction of ImageBitmaps that are created from ImageElements.

Source/core/loader/cache/CachedResource.cpp

Index: Source/core/loader/cache/CachedResource.cpp
diff --git a/Source/core/loader/cache/CachedResource.cpp b/Source/core/loader/cache/CachedResource.cpp
index e981ad4deae249553e3ac14940b419d9f6bb82f7..74e69b40bca7ce16eb19ca2618d8d9cdb2b457c4 100644
--- a/Source/core/loader/cache/CachedResource.cpp
+++ b/Source/core/loader/cache/CachedResource.cpp
@@ -105,7 +105,7 @@ static inline bool shouldUpdateHeaderAfterRevalidation(const AtomicString& heade
 
 DEFINE_DEBUG_ONLY_GLOBAL(RefCountedLeakCounter, cachedResourceLeakCounter, ("CachedResource"));
 
-CachedResource::CachedResource(const ResourceRequest& request, Type type)
+CachedResource::CachedResource(const ResourceRequest& request, Type type, DecodeCachePriority decodeCachePriority)

[Justin Novosad, 2013/07/19 21:09:53]

No need for extra construction arg. Just initialize with low priority by
default. Client code can raise priority explicitly if needed.

     : m_resourceRequest(request)
     , m_responseTimestamp(currentTime())
     , m_decodedDataDeletionTimer(this, &CachedResource::decodedDataDeletionTimerFired)
@@ -119,6 +119,7 @@ CachedResource::CachedResource(const ResourceRequest& request, Type type)
     , m_handleCount(0)
     , m_preloadCount(0)
     , m_preloadResult(PreloadNotReferenced)
+    , m_decodeCachePriority(decodeCachePriority)
     , m_inLiveDecodedResourcesList(false)
     , m_requestedFromNetworkingLayer(false)
     , m_inCache(false)
@@ -881,3 +882,4 @@ void CachedResource::reportMemoryUsage(MemoryObjectInfo* memoryObjectInfo) const
         info.addRawBuffer(m_purgeableData.get(), m_purgeableData->size(), "PurgeableData", "purgeableData");
 }
 }
+