Don't show a placeholder if the response contains the full image.

third_party/WebKit/Source/platform/network/HTTPParsers.h

Index: third_party/WebKit/Source/platform/network/HTTPParsers.h
diff --git a/third_party/WebKit/Source/platform/network/HTTPParsers.h b/third_party/WebKit/Source/platform/network/HTTPParsers.h
index a4941d8d1d6010c285d6f726ebd0e097680f2583..29790949335a5562132c9e4c2f009c4ea7aac5f0 100644
--- a/third_party/WebKit/Source/platform/network/HTTPParsers.h
+++ b/third_party/WebKit/Source/platform/network/HTTPParsers.h
@@ -40,6 +40,7 @@
 #include "wtf/text/StringHash.h"
 
 #include <memory>
+#include <stdint.h>
 
 namespace blink {
 
@@ -168,6 +169,18 @@ PLATFORM_EXPORT bool parseMultipartHeadersFromBody(const char* bytes,
 PLATFORM_EXPORT std::unique_ptr<JSONArray> parseJSONHeader(const String& header,
                                                            int maxParseDepth);
 
+// Extracts the values in a Content-Range header and returns true if they are
+// valid for a 206 response; otherwise returns false.
+// The following values will be outputted:
+// |*firstBytePosition| = inclusive position of the first byte of the range
+// |*lastBytePosition| = inclusive position of the last byte of the range
+// |*instanceLength| = size in bytes of the object requested
+// If any of the above values is unknown, its value will be -1.
+PLATFORM_EXPORT bool parseContentRangeHeader(const String& contentRange,
+                                             int64_t* firstBytePosition,
+                                             int64_t* lastBytePosition,
+                                             int64_t* instanceLength);
+
 }  // namespace blink
 
 #endif