Update ICU bug url in README.chromium

ICU bug tracker moved to Jira. Update bug urls referred to in
README.chromium

https://unicode-org.atlassian.net/browse/ICU-{bug #}

Bug: None
Test: None
Change-Id: I12bfdc9c011293b1ee066ae689fd662df1c74d94
Reviewed-on: https://chromium-review.googlesource.com/1146488
Reviewed-by: Jungshik Shin <jshin@chromium.org>

Author: jungshik

README.chromium

@@ -39,7 +39,7 @@ Pre-built data files are generated and checked in with the following steps
 
   c. Run make
      'make' will fail  when pkgdata looks for root_subset.res. This
-     is expected. See https://ssl.icu-project.org/trac/ticket/10570
+     is expected. See https://unicode-org.atlassian.net/browse/ICU-10570
 
   d. Run
        ${CHROME_ICU_TREE_TOP}/scripts/make_data_all.sh
@@ -146,7 +146,7 @@ them when updating ICU.
 
 3. source/data/brkitr
   - dictionaries/khmerdict.txt: Abridged Khmer dictionary. See
-    https://ssl.icu-project.org/trac/ticket/9451
+    https://unicode-org.atlassian.net/browse/ICU-9451
   - rules/word_ja.txt (used only on Android)
     Added for Japanese-specific word-breaking without the C+J dictionary.
   - rules/{fi,root,zh,zh_Hant}.txt
@@ -189,12 +189,12 @@ D. Local Modifications
 
   - patches/khmer-dictbe.patch
     Adjust parameters to use a smaller Khmer dictionary (khmerdict.txt).
-    https://ssl.icu-project.org/trac/ticket/9451
+    https://unicode-org.atlassian.net/browse/ICU-9451
 
   - Add several common Chinese words that were dropped previously to
     source/data/cjdict/brkitr/cjdict.txt
     patch: patches/cjdict.patch
-    upstream bug: https://ssl.icu-project.org/trac/ticket/10888
+    upstream bug: https://unicode-org.atlassian.net/browse/ICU-10888
 
 3. Timezone data update
   Run scripts/update_tz.sh to grab the latest version of the
@@ -212,8 +212,8 @@ D. Local Modifications
 4. Build-related changes
 
   - patches/wpo.patch (only needed when icudata dll is used).
-    upstream bugs : https://ssl.icu-project.org/trac/ticket/8043
-                    https://ssl.icu-project.org/trac/ticket/5701
+    upstream bugs : https://unicode-org.atlassian.net/browse/ICU-8043
+                    https://unicode-org.atlassian.net/browse/ICU-5701
   - patches/vscomp.patch for building with Visual Studio on Windows:
     do not use WINDOWS_LOCALE_API in locmap.c
 
@@ -228,35 +228,35 @@ D. Local Modifications
 5. Fix -Wsign-compare warning in EnumSet::isValidEnum()
 
   - patches/isvalidenum.patch
-    upstream bug: https://ssl.icu-project.org/trac/ticket/13509
+    upstream bug: https://unicode-org.atlassian.net/browse/ICU-13509
 
 7. Update IANA language tag/subtag mapping and add missing canonicalization for
     deprecated regions
 
   - patches/locid_map.patch
   - upstream bugs:
-    https://ssl.icu-project.org/trac/ticket/13726
-    https://ssl.icu-project.org/trac/ticket/13723
-    https://ssl.icu-project.org/trac/ticket/13721
-    https://ssl.icu-project.org/trac/ticket/13720
-    https://ssl.icu-project.org/trac/ticket/13719
+    https://unicode-org.atlassian.net/browse/ICU-13726
+    https://unicode-org.atlassian.net/browse/ICU-13723
+    https://unicode-org.atlassian.net/browse/ICU-13721
+    https://unicode-org.atlassian.net/browse/ICU-13720
+    https://unicode-org.atlassian.net/browse/ICU-13719
 
 8. Double conversion library build failure
 
   - patches/double_conversion.patch
   - upstream bugs:
-    https://ssl.icu-project.org/trac/ticket/13750
+    https://unicode-org.atlassian.net/browse/ICU-13750
     https://github.com/google/double-conversion/issues/66
 
 9. Cherry-pick Greek lowercase fix from the upstream
 
   - patches/greek_lowercase.patch
   - upstream bug (fixed in 62.2-to-be)
-    https://ssl.icu-project.org/trac/ticket/13851
+    https://unicode-org.atlassian.net/browse/ICU-13851
 
 10. Max significant digit is always 6
 
   - patches/nf_maxsig.patch
   - upstream bug:
-    https://ssl.icu-project.org/trac/ticket/13852
+    https://unicode-org.atlassian.net/browse/ICU-13852