Reverts third_party/protobuf: Update to HEAD (f52e188fe4)

third_party/protobuf/benchmarks/readme.txt

Index: third_party/protobuf/benchmarks/readme.txt
diff --git a/third_party/protobuf/benchmarks/readme.txt b/third_party/protobuf/benchmarks/readme.txt
index b08b8bc09cabadf3fb5dff17fc223cac206376ed..2c836d0a1cfb2d6adaf19e7dec369cd749c53849 100644
--- a/third_party/protobuf/benchmarks/readme.txt
+++ b/third_party/protobuf/benchmarks/readme.txt
@@ -22,25 +22,29 @@ Running a benchmark (Java)
    $ javac -d tmp -cp protobuf.jar ProtoBench.java
    
 3) Generate code for the relevant benchmark protocol buffer, e.g.
-   $ protoc --java_out=tmp google_size.proto
+   $ protoc --java_out=tmp google_size.proto google_speed.proto
    
 4) Build the generated code, e.g.
-   $ javac -d tmp -cp protobuf.jar tmp/benchmarks/*.java
+   $ cd tmp
+   $ javac -d . -cp ../protobuf.jar benchmarks/*.java
            
 5) Run the test. Arguments are given in pairs - the first argument
    is the descriptor type; the second is the filename. For example:
-   $ java -cp tmp:protobuf.jar com.google.protocolbuffers.ProtoBench \
-       'benchmarks.GoogleSize$SizeMessage1' google_message1.dat \
-       'benchmarks.GoogleSize$SizeMessage2' google_message2.dat
+   $ java -cp .;../protobuf.jar com.google.protocolbuffers.ProtoBench
+          benchmarks.GoogleSize$SizeMessage1 ../google_message1.dat
+          benchmarks.GoogleSpeed$SpeedMessage1 ../google_message1.dat
+          benchmarks.GoogleSize$SizeMessage2 ../google_message2.dat
+          benchmarks.GoogleSpeed$SpeedMessage2 ../google_message2.dat
           
-6) Wait! Each test runs for around 30 seconds, and there are 8 tests
+6) Wait! Each test runs for around 30 seconds, and there are 6 tests
    per class/data combination. The above command would therefore take
-   about 8 minutes to run.
+   about 12 minutes to run.
 
    
 Benchmarks available
 --------------------
 
 From Google:
-google_size.proto,
-messages google_message1.dat and google_message2.dat.
+google_size.proto and google_speed.proto, messages
+google_message1.dat and google_message2.dat. The proto files are
+equivalent, but optimized differently.