Bump up travis to Xcode 7.2

- Update simulator versions used.
- Mark the iOS tests as flaky while trying to dig out the root cause.
diff --git a/.travis.yml b/.travis.yml
index e368826..c0309fa 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -7,8 +7,8 @@
 os:
   - linux
   - osx
-# The Objective C build needs Xcode 6.4 or later.
-osx_image: xcode7.1
+# The Objective C build needs Xcode 7.0 or later.
+osx_image: xcode7.2
 script:
   - ./travis.sh $CONFIG
 env:
@@ -67,5 +67,8 @@
       env: CONFIG=ruby22
     - os: osx
       env: CONFIG=jruby
+    # Currently showing flake randomly, doesn't trace back to a single commit.
+    - os: osx
+      env: CONFIG=objectivec_ios
 notifications:
   email: false
diff --git a/objectivec/DevTools/full_mac_build.sh b/objectivec/DevTools/full_mac_build.sh
index 709aae0..c8681e2 100755
--- a/objectivec/DevTools/full_mac_build.sh
+++ b/objectivec/DevTools/full_mac_build.sh
@@ -234,7 +234,7 @@
       echo "ERROR: Xcode 6.3/6.4 no longer supported for building, please use 7.0 or higher." 1>&2
       exit 10
       ;;
-    7.* )
+    7.1* )
       XCODEBUILD_TEST_BASE_IOS+=(
           -destination "platform=iOS Simulator,name=iPhone 4s,OS=8.1" # 32bit
           -destination "platform=iOS Simulator,name=iPhone 6,OS=9.0" # 64bit
@@ -242,6 +242,14 @@
           -destination "platform=iOS Simulator,name=iPad Air,OS=9.0" # 64bit
       )
       ;;
+    7.* )
+      XCODEBUILD_TEST_BASE_IOS+=(
+          -destination "platform=iOS Simulator,name=iPhone 4s,OS=8.1" # 32bit
+          -destination "platform=iOS Simulator,name=iPhone 6,OS=9.2" # 64bit
+          -destination "platform=iOS Simulator,name=iPad 2,OS=8.1" # 32bit
+          -destination "platform=iOS Simulator,name=iPad Air,OS=9.2" # 64bit
+      )
+      ;;
     * )
       echo "Time to update the simulator targets for Xcode ${XCODE_VERSION}"
       exit 2
diff --git a/travis.sh b/travis.sh
index 5a77a2a..13a109a 100755
--- a/travis.sh
+++ b/travis.sh
@@ -195,9 +195,9 @@
     build-tests
   IOS_DESTINATIONS=(
     "platform=iOS Simulator,name=iPhone 4s,OS=8.1" # 32bit
-    "platform=iOS Simulator,name=iPhone 6,OS=9.1" # 64bit
+    "platform=iOS Simulator,name=iPhone 6,OS=9.2" # 64bit
     "platform=iOS Simulator,name=iPad 2,OS=8.1" # 32bit
-    "platform=iOS Simulator,name=iPad Air,OS=9.1" # 64bit
+    "platform=iOS Simulator,name=iPad Air,OS=9.2" # 64bit
   )
   for i in "${IOS_DESTINATIONS[@]}" ; do
     internal_xctool_debug_and_release \