Prepopulate the memoryCache with data:uri images.

Source/core/loader/cache/CachedResourceLoader.cpp

Index: Source/core/loader/cache/CachedResourceLoader.cpp
diff --git a/Source/core/loader/cache/CachedResourceLoader.cpp b/Source/core/loader/cache/CachedResourceLoader.cpp
index b5ca77c14353e4b5fd59767861482c1cb8e02bd3..0305f6406038f1908cb1e12da19b96afb367c1e9 100644
--- a/Source/core/loader/cache/CachedResourceLoader.cpp
+++ b/Source/core/loader/cache/CachedResourceLoader.cpp
@@ -50,6 +50,7 @@
 #include "core/loader/cache/CachedResourceRequest.h"
 #include "core/loader/cache/CachedScript.h"
 #include "core/loader/cache/CachedShader.h"
+#include "core/loader/cache/CachedTextTrack.h"
 #include "core/loader/cache/CachedXSLStyleSheet.h"
 #include "core/loader/cache/MemoryCache.h"
 #include "core/page/Console.h"
@@ -59,11 +60,11 @@
 #include "core/page/Performance.h"
 #include "core/page/Settings.h"
 #include "core/platform/Logging.h"
+#include "public/platform/Platform.h"
+#include "public/platform/WebURL.h"
 #include "weborigin/SecurityOrigin.h"
 #include "weborigin/SecurityPolicy.h"
 
-#include "core/loader/cache/CachedTextTrack.h"
-
 #define PRELOAD_DEBUG 0
 
 namespace WebCore {
@@ -99,6 +100,26 @@ static CachedResource* createResource(CachedResource::Type type, ResourceRequest
     return 0;
 }
 
+static CachedResource* resourceFromDataURIRequest(ResourceRequest& request)
+{
+    KURL url = request.url();

[abarth-chromium, 2013/06/05 23:42:51]

this can be a const KURL& rather than a KURL

[pdr., 2013/06/05 23:53:25]

Done.

+    ASSERT(url.protocolIsData());
+
+    WebKit::WebString mimetype;
+    WebKit::WebString charset;
+    RefPtr<SharedBuffer> data = PassRefPtr<SharedBuffer>(WebKit::Platform::current()->parseDataURL(url, mimetype, charset));
+    if (!data || !data->size())

[abarth-chromium, 2013/06/05 23:42:51]

Checking the size here doesn't seem right.  It's better to no call appendData if
there isn't any data.

[pdr., 2013/06/05 23:53:25]

Done.

+        return 0;
+    ResourceResponse response(url, mimetype, data->size(), charset, String());
+
+    CachedResource* resource = createResource(CachedResource::ImageResource, request, charset);
+    resource->responseReceived(response);
+    // FIXME: This is an unnecessary memcpy.
+    resource->appendData(data->data(), data->size());
+    resource->finish();
+    return resource;
+}
+
 CachedResourceLoader::CachedResourceLoader(DocumentLoader* documentLoader)
     : m_document(0)
     , m_documentLoader(documentLoader)
@@ -148,10 +169,29 @@ CachedResourceHandle<CachedImage> CachedResourceLoader::requestImage(CachedResou
             return 0;
         }
     }
+
+    if (request.resourceRequest().url().protocolIsData())
+        preCacheDataURIImage(request);

[Nate Chapin, 2013/06/05 23:50:54]

Should this early return? Otherwise, won't we run the request normally in
addition?

[pdr., 2013/06/05 23:53:25]

That's the idea: we pre-populate the memory cache and then run the request
normally. This prevents us from having to duplicate some of the loader logic.

+
     request.setDefer(clientDefersImage(request.resourceRequest().url()) ? CachedResourceRequest::DeferredByClient : CachedResourceRequest::NoDefer);
     return static_cast<CachedImage*>(requestResource(CachedResource::ImageResource, request).get());
 }
 
+void CachedResourceLoader::preCacheDataURIImage(CachedResourceRequest& request)
+{
+    KURL url = request.resourceRequest().url();

[abarth-chromium, 2013/06/05 23:42:51]

const KURL&

[pdr., 2013/06/05 23:53:25]

Done.

+    ASSERT(url.protocolIsData());
+
+    if (CachedResource* existing = memoryCache()->resourceForURL(url)) {
+        if (existing->type() == CachedResource::ImageResource)
+            return;
+        memoryCache()->remove(existing); // Cache entry is incorrect.
+    }
+
+    if (CachedResource* resource = resourceFromDataURIRequest(request.mutableResourceRequest()))
+        memoryCache()->add(resource);
+}
+
 CachedResourceHandle<CachedFont> CachedResourceLoader::requestFont(CachedResourceRequest& request)
 {
     return static_cast<CachedFont*>(requestResource(CachedResource::FontResource, request).get());