Fix clang-tidy warnings in aapt and aapt2.

* Add explicit keyword to conversion constructors.
* Add NOLINT(implicit) comments for implicit conversion constructors.
Bug: 28341362
* Use const reference type for read-only parameters.
Bug: 30407689
* Use const reference type to avoid unnecessary copy.
Bug: 30413862
Test: build with WITH_TIDY=1

Change-Id: Id6d21961f313a1ad92b15a37fdaa5be9e8ab48e1
Merged-In: Id6d21961f313a1ad92b15a37fdaa5be9e8ab48e1

tools/aapt2/JavaClassGenerator_test.cpp

@@ -35,7 +35,7 @@ struct JavaClassGeneratorTest : public ::testing::Test {
         mTable->setPackageId(0x01);
     }
 
-    bool addResource(const ResourceNameRef& name, ResourceId id) {
+    bool addResource(const ResourceNameRef& name, const ResourceId& id) {
         return mTable->addResource(name, id, {}, SourceLine{ "test.xml", 21 },
                                    util::make_unique<Id>());
     }