Bug 1092857 - Drop conditional request headers when there is no cache entry available. r=michal

netwerk/protocol/http/nsHttpChannel.cpp

@@ -2854,6 +2854,15 @@ nsHttpChannel::CheckPartial(nsICacheEntry* aEntry, int64_t *aSize, int64_t *aCon
     return NS_OK;
 }
 
+void
+nsHttpChannel::UntieValidationRequest()
+{
+    // Make the request unconditional again.
+    mRequestHead.ClearHeader(nsHttp::If_Modified_Since);
+    mRequestHead.ClearHeader(nsHttp::If_None_Match);
+    mRequestHead.ClearHeader(nsHttp::ETag);
+}
+
 NS_IMETHODIMP
 nsHttpChannel::OnCacheEntryCheck(nsICacheEntry* entry, nsIApplicationCache* appCache,
                                  uint32_t* aResult)
@@ -3205,10 +3214,7 @@ nsHttpChannel::OnCacheEntryCheck(nsICacheEntry* entry, nsIApplicationCache* appC
             // If we can't get the entity then we have to act as though we
             // don't have the cache entry.
             if (mDidReval) {
-                // Make the request unconditional again.
-                mRequestHead.ClearHeader(nsHttp::If_Modified_Since);
-                mRequestHead.ClearHeader(nsHttp::If_None_Match);
-                mRequestHead.ClearHeader(nsHttp::ETag);
+                UntieValidationRequest();
                 mDidReval = false;
             }
             mCachedContentIsValid = false;
@@ -3299,12 +3305,14 @@ nsHttpChannel::OnCacheEntryAvailableInternal(nsICacheEntry *entry,
         return NS_ERROR_DOCUMENT_NOT_CACHED;
     }
 
-    if (NS_FAILED(rv))
-      return rv;
+    if (NS_FAILED(rv)) {
+        return rv;
+    }
 
     // We may be waiting for more callbacks...
-    if (AwaitingCacheCallbacks())
-      return NS_OK;
+    if (AwaitingCacheCallbacks()) {
+        return NS_OK;
+    }
 
     return ContinueConnect();
 }
@@ -3321,6 +3329,14 @@ nsHttpChannel::OnNormalCacheEntryAvailable(nsICacheEntry *aEntry,
         // between OnCacheEntryCheck and OnCacheEntryAvailable.
         mCachedContentIsValid = false;
 
+        // From the same reason remove any conditional headers added
+        // in OnCacheEntryCheck.
+        if (mDidReval) {
+            LOG(("  Removing conditional request headers"));
+            UntieValidationRequest();
+            mDidReval = false;
+        }
+
         if (mLoadFlags & LOAD_ONLY_FROM_CACHE) {
             // if this channel is only allowed to pull from the cache, then
             // we must fail if we were unable to open a cache entry for read.

netwerk/protocol/http/nsHttpChannel.h

@@ -368,6 +368,7 @@ private:
                                         bool ignoreMissingPartialLen = false);
     nsresult SetupByteRangeRequest(int64_t partialLen);
     void UntieByteRangeRequest();
+    void UntieValidationRequest();
     nsresult OpenCacheInputStream(nsICacheEntry* cacheEntry, bool startBuffering,
                                   bool checkingAppCacheEntry);