[Blob] Dependencies for blob storage testing

public/platform/WebBlobRegistry.h

Index: public/platform/WebBlobRegistry.h
diff --git a/public/platform/WebBlobRegistry.h b/public/platform/WebBlobRegistry.h
index 7dac23d2d1591f6587d7cbb0ac4016c9629b1682..5c9df4d39f965e4c1e013f9dcb90e6e86118e810 100644
--- a/public/platform/WebBlobRegistry.h
+++ b/public/platform/WebBlobRegistry.h
@@ -32,6 +32,7 @@
 #define WebBlobRegistry_h
 
 #include "WebCommon.h"
+#include "WebThreadSafeData.h"
 
 namespace blink {
 
@@ -39,11 +40,45 @@ class WebBlobData;
 class WebString;
 class WebURL;
 
+// Acts as singleton facade for all Blob interactions ouside of blink.  This
+// includes blob:
+// * creation,
+// * reference counting,
+// * publishing, and
+// * streaming.
 class WebBlobRegistry {
 public:
+    // Builder class for creating blobs. The blob is built on calling the
+    // build() method, where IPCs are sent to the browser.
+    // Preconditions:
+    // * Not meant to be used on multiple threads.
+    // * Must not be kept alive longer than creator WebBlobRegistry (shouldn't
+    //   be an issue because of the singleton nature of the WebBlobRegistry)
+    // * append.* methods are invalid after build() is called.
+    class Builder {
+    public:
+        virtual ~Builder() { }
+        virtual void appendData(const WebThreadSafeData&) = 0;
+        virtual void appendFile(const WebString& path, uint64_t offset, uint64_t length, double expectedModificationTime) = 0;
+        // Calling this method ensures the given blob lives for the creation of
+        // the new blob.
+        virtual void appendBlob(const WebString& uuid, uint64_t offset, uint64_t length) = 0;
+        virtual void appendFileSystemURL(const WebURL&, uint64_t offset, uint64_t length, double expectedModificationTime) = 0;
+
+        // Builds the blob. All calls to append* are invalid after calling this
+        // method.
+        virtual void build() = 0;
+    };
+
     virtual ~WebBlobRegistry() { }
 
+    // TODO(dmurph): Deprecate and migrate to createBuilder
     virtual void registerBlobData(const WebString& uuid, const WebBlobData&) { }
+
+    // Caller takes ownership of the Builder. The blob is finalized (and sent to
+    // the browser) on calling build() on the Builder object.
+    virtual Builder* createBuilder(const WebString& uuid, const WebString& contentType) { BLINK_ASSERT_NOT_REACHED(); return nullptr; }
+
     virtual void addBlobDataRef(const WebString& uuid) { }
     virtual void removeBlobDataRef(const WebString& uuid) { }
     virtual void registerPublicBlobURL(const WebURL&, const WebString& uuid) { }