Minor cleanup in SpdyFrameBuilder. No functional/compiled change.

This lands server change 42070470.

Review URL: https://codereview.chromium.org/12262002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@182429 0039d316-1c4b-4281-b951-d872f2087c98

net/spdy/spdy_frame_reader.cc

@@ -69,7 +69,7 @@ bool SpdyFrameReader::ReadUInt31(uint32* result) {
 
   // Zero out highest-order bit.
   if (success) {
-    *result &= kStreamIdMask;
+    *result &= 0x7fffffff;
   }
 
   return success;

net/spdy/spdy_frame_reader.h

@@ -49,7 +49,7 @@ class NET_EXPORT_PRIVATE SpdyFrameReader {
   bool ReadUInt32(uint32* result);
 
   // Reads a 31-bit unsigned integer into the given output parameter. This is
-  // equivelant to ReadUInt32() above except that the highest-order bit is
+  // equivalent to ReadUInt32() above except that the highest-order bit is
   // discarded.
   // Forwards the internal iterater (by 4B) on success.
   // Returns true on success, false otherwise.