Update chardet from 3.0.3 to 3.0.4 (#2545)

requirements/common.txt

@@ -175,7 +175,9 @@ certifi==2017.4.17 \
     --hash=sha256:f7527ebf7461582ce95f7a9e03dd141ce810d40590834f4ec20cddd54234c10a
 
 # required by requests
-chardet==3.0.3 --hash=sha256:8da3f329e2c5779247f4cff7081512c531731ef6a9c6ef78084e8ed8d18226c7
+chardet==3.0.4 \
+    --hash=sha256:fc323ffcaeaed0e0a02bf4d117757b98aed530d9ed4531e3e15460124c106691 \
+    --hash=sha256:84ab92ed1c4d4f16916e05906b6b75a6c0fb5db821cc65e70cbd64a3e2a5eaae
 idna==2.5 --hash=sha256:cc19709fd6d0cbfed39ea875d29ba6d4e22c0cebc510a76d6302a28385e8bb70
 
 # required for taskcluster