[GR-8261] [GR-8262] [GR-8050] Remove PolyglotEngine references and various other fixes.

...le.r.native/fficall/src/truffle_common/variables_common.h

...oracle/truffle/r/nodes/builtin/base/BitwiseFunctions.java

...com/oracle/truffle/r/nodes/builtin/base/EncodeString.java

...om/oracle/truffle/r/nodes/builtin/fastr/FastRContext.java

...e/truffle/r/nodes/builtin/fastr/memprof/FastRprofmem.java

...uffle/r/nodes/builtin/fastr/memprof/FastRprofmemShow.java

...fle/r/nodes/builtin/fastr/memprof/FastRprofmemSource.java

...fle.r.nodes/src/com/oracle/truffle/r/nodes/RASTUtils.java

...acle/truffle/r/nodes/function/call/RExplicitCallNode.java

...untime/src/com/oracle/truffle/r/runtime/FastROptions.java

....r.runtime/src/com/oracle/truffle/r/runtime/REnvVars.java

...om/oracle/truffle/r/runtime/context/ChildContextInfo.java

...time/src/com/oracle/truffle/r/runtime/context/Engine.java

.../src/com/oracle/truffle/r/runtime/context/EvalThread.java

...me/src/com/oracle/truffle/r/runtime/context/RContext.java

...est/src/com/oracle/truffle/r/test/ExpectedTestOutput.test

.../oracle/truffle/r/test/builtins/TestBuiltin_asvector.java

.../com/oracle/truffle/r/test/builtins/TestBuiltin_attr.java

...racle/truffle/r/test/builtins/TestBuiltin_bitwiseNot.java

...rc/com/oracle/truffle/r/test/builtins/TestBuiltin_lm.java