Add fuzzer to test Fuzz URLRequestDataJob

net/base/fuzzed_data_provider.cc

Index: net/base/fuzzed_data_provider.cc
diff --git a/net/base/fuzzed_data_provider.cc b/net/base/fuzzed_data_provider.cc
index 6278ff2ff9a1363aa2922763e5b485c8f59c2cfa..4d13e6f1f70993dd50f32de2077fc9bb7d970290 100644
--- a/net/base/fuzzed_data_provider.cc
+++ b/net/base/fuzzed_data_provider.cc
@@ -23,6 +23,10 @@ size_t FuzzedDataProvider::ConsumeBytes(char* dest, size_t bytes) {
   return bytes_to_write;
 }
 
+size_t FuzzedDataProvider::ConsumeRemainingBytes(char* dest) {

[Charlie Harrison, 2016/04/26 12:58:40]

This is wrong, because we could buffer overflow dest.

+  return ConsumeBytes(dest, remaining_bytes());
+}
+
 uint32_t FuzzedDataProvider::ConsumeBits(size_t num_bits) {
   CHECK_NE(0u, num_bits);
   CHECK_LE(num_bits, 32u);
@@ -38,7 +42,7 @@ uint32_t FuzzedDataProvider::ConsumeBits(size_t num_bits) {
       bits_to_add = num_bits;
     new_bits &= new_bits & ((1 << bits_to_add) - 1);
     out = (out << bits_to_add) | new_bits;
-    num_bits -= bits_to_add;
+    num_bits = num_bits > bits_to_add ? num_bits - bits_to_add : 0;

[Charlie Harrison, 2016/04/26 12:58:40]

Temporary fix.

   }
 
   return out;