Turn compareJsDoc on in all unit tests

git grep "compareJsDoc = false" gives:

test/com/google/javascript/jscomp/AmbiguatePropertiesTest.java: compareJsDoc = false;
~~test/com/google/javascript/jscomp/AngularPassTest.java: compareJsDoc = false;~~
test/com/google/javascript/jscomp/CheckAccessControlsTest.java: compareJsDoc = false;
test/com/google/javascript/jscomp/CollapsePropertiesTest.java: compareJsDoc = false;
test/com/google/javascript/jscomp/CollapseVariableDeclarationsTest.java: compareJsDoc = false;
~~test/com/google/javascript/jscomp/DevirtualizePrototypeMethodsTest.java: compareJsDoc = false;~~
test/com/google/javascript/jscomp/Es6InlineTypesTest.java: compareJsDoc = false;
test/com/google/javascript/jscomp/GenerateExportsTest.java: compareJsDoc = false;
~~test/com/google/javascript/jscomp/InferJSDocInfoTest.java: compareJsDoc = false;~~
~~test/com/google/javascript/jscomp/InlinePropertiesTest.java: compareJsDoc = false;~~
test/com/google/javascript/jscomp/InlineVariablesTest.java: compareJsDoc = false;
test/com/google/javascript/jscomp/JsdocToEs6TypedConverterTest.java: compareJsDoc = false;
~~test/com/google/javascript/jscomp/NormalizeTest.java: compareJsDoc = false;~~
~~test/com/google/javascript/jscomp/OptimizeParametersTest.java: compareJsDoc = false;~~
~~test/com/google/javascript/jscomp/ProcessCommonJSModulesTest.java: compareJsDoc = false;~~
test/com/google/javascript/jscomp/ProcessDefinesTest.java: compareJsDoc = false;
test/com/google/javascript/jscomp/RemoveUnusedVarsTest.java: compareJsDoc = false;
test/com/google/javascript/jscomp/RenameVarsTest.java: compareJsDoc = false;
test/com/google/javascript/jscomp/ReplaceIdGeneratorsTest.java: compareJsDoc = false;
test/com/google/javascript/jscomp/ReplaceMessagesForChromeTest.java: compareJsDoc = false;
test/com/google/javascript/jscomp/ReplaceMessagesTest.java: compareJsDoc = false;
test/com/google/javascript/jscomp/ReplaceStringsTest.java: compareJsDoc = false;
test/com/google/javascript/jscomp/RuntimeTypeCheckTest.java: compareJsDoc = false;
~~test/com/google/javascript/jscomp/VarCheckTest.java: compareJsDoc = false;~~

We should eventually turn it on for all of them and remove the compareJsDoc field.