ICU-21249 add hide-draft guards for some @draft ICU 68 API

icu4c/source/common/unicode/utypes.h

@@ -479,6 +479,7 @@ typedef enum UErrorCode {
     U_COLLATOR_VERSION_MISMATCH = 28,   /**< Collator version is not compatible with the base version */
     U_USELESS_COLLATOR_ERROR  = 29,     /**< Collator is options only and no base is specified */
     U_NO_WRITE_PERMISSION     = 30,     /**< Attempt to modify read-only or constant data. */
+#ifndef U_HIDE_DRAFT_API
     /**
      * The input is impractically long for an operation.
      * It is rejected because it may lead to problems such as excessive
@@ -487,13 +488,14 @@ typedef enum UErrorCode {
      * @draft ICU 68
      */
     U_INPUT_TOO_LONG_ERROR = 31,
+#endif  // U_HIDE_DRAFT_API
 
 #ifndef U_HIDE_DEPRECATED_API
     /**
      * One more than the highest standard error code.
      * @deprecated ICU 58 The numeric value may change over time, see ICU ticket #12420.
      */
-    U_STANDARD_ERROR_LIMIT,
+    U_STANDARD_ERROR_LIMIT = 32,
 #endif  // U_HIDE_DEPRECATED_API
 
     /*

icu4c/source/i18n/unicode/dtitvfmt.h

@@ -652,6 +652,7 @@ public:
      */
     virtual void setTimeZone(const TimeZone& zone);
 
+#ifndef U_FORCE_HIDE_DRAFT_API
     /**
      * Set a particular UDisplayContext value in the formatter, such as
      * UDISPCTX_CAPITALIZATION_FOR_STANDALONE. This causes the formatted
@@ -677,6 +678,7 @@ public:
      * @draft ICU 68
      */
     virtual UDisplayContext getContext(UDisplayContextType type, UErrorCode& status) const;
+#endif  // U_FORCE_HIDE_DRAFT_API
 
     /**
      * Return the class ID for this class. This is useful only for comparing to

icu4c/source/test/hdrtst/testtagsguards.sh

@@ -2,7 +2,7 @@
 # License & terms of use: http://www.unicode.org/copyright.html
 
 # Run this script from $ICU_ROOT/icu4c.
-# ~/icu/mine/src/icu4c$ source/test/hdrtest/testtagsguards.sh
+# ~/icu/mine/src/icu4c$ source/test/hdrtst/testtagsguards.sh
 
 # set -x # echo on