Reland "ios: Remove IsSpuriousMessage logic."

This is a reland of 7ff16d5783.

Also removes a dangling 76x76@1 image, as 76x76@1x app icons only apply
to iPad apps targeting releases of iOS prior to 10.0.

Original change's description:
> ios: Remove IsSpuriousMessage logic.
>
> Bug: 1223072
> Change-Id: Ibd700596cf7da5da3b7586960701b7668d210b40
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2983778
> Reviewed-by: Sylvain Defresne <sdefresne@chromium.org>
> Commit-Queue: Justin Cohen <justincohen@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#895676}

Bug: 1223072
Change-Id: I843773ddfba5fbef9671a2f58f52d4008be14bff
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2982871
Reviewed-by: Yuwei Huang <yuweih@chromium.org>
Reviewed-by: Sylvain Defresne <sdefresne@chromium.org>
Auto-Submit: Justin Cohen <justincohen@chromium.org>
Commit-Queue: Sylvain Defresne <sdefresne@chromium.org>
Cr-Commit-Position: refs/heads/master@{#895997}

build/toolchain/ios/compile_xcassets.py

@@ -30,26 +30,6 @@ SECTION_HEADER = re.compile('^/\\* ([^ ]*) \\*/$')
 # Name of the section containing informational messages that can be ignored.
 NOTICE_SECTION = 'com.apple.actool.compilation-results'
 
-# Regular expressions matching spurious messages from actool that should be
-# ignored (as they are bogus). Generally a bug should be filed with Apple
-# when adding a pattern here.
-SPURIOUS_PATTERNS = [
-    re.compile(v) for v in [
-        # crbug.com/770634, likely a bug in Xcode 9.1 beta, remove once build
-        # requires a version of Xcode with a fix.
-        r'\[\]\[ipad\]\[76x76\]\[\]\[\]\[1x\]\[\]\[\]: notice: \(null\)',
-
-        # crbug.com/770634, likely a bug in Xcode 9.2 beta, remove once build
-        # requires a version of Xcode with a fix.
-        r'\[\]\[ipad\]\[76x76\]\[\]\[\]\[1x\]\[\]\[\]: notice: 76x76@1x app'
-        ' icons only apply to iPad apps targeting releases of iOS prior to'
-        ' 10.0.',
-        r'\[\]\[ipad\]\[76x76\]\[\]\[\]\[1x\]\[\]\[\]\[\]: notice: 76x76@1x app'
-        ' icons only apply to iPad apps targeting releases of iOS prior to'
-        ' 10.0.',
-    ]
-]
-
 # Map special type of asset catalog to the corresponding command-line
 # parameter that need to be passed to actool.
 ACTOOL_FLAG_FOR_ASSET_TYPE = {
@@ -57,16 +37,6 @@ ACTOOL_FLAG_FOR_ASSET_TYPE = {
     '.launchimage': '--launch-image',
 }
 
-
-def IsSpuriousMessage(line):
-  """Returns whether line contains a spurious message that should be ignored."""
-  for pattern in SPURIOUS_PATTERNS:
-    match = pattern.search(line)
-    if match is not None:
-      return True
-  return False
-
-
 def FixAbsolutePathInLine(line, relative_paths):
   """Fix absolute paths present in |line| to relative paths."""
   absolute_path = line.split(':')[0]
@@ -114,8 +84,6 @@ def FilterCompilerOutput(compiler_output, relative_paths):
       current_section = match.group(1)
       continue
     if current_section and current_section != NOTICE_SECTION:
-      if IsSpuriousMessage(line):
-        continue
       if not data_in_section:
         data_in_section = True
         filtered_output.append('/* %s */\n' % current_section)

remoting/ios/app/resources/BUILD.gn

@@ -79,7 +79,6 @@ appiconset("remoting_icons") {
     "chromium/AppIcon.appiconset/Icon-29.png",
     "chromium/AppIcon.appiconset/Icon-40.png",
     "chromium/AppIcon.appiconset/Icon-58.png",
-    "chromium/AppIcon.appiconset/Icon-76.png",
     "chromium/AppIcon.appiconset/Icon-80.png",
     "chromium/AppIcon.appiconset/Icon-87.png",
   ]

remoting/ios/app/resources/chromium/AppIcon.appiconset/Contents.json

@@ -80,12 +80,6 @@
       "filename" : "Icon-80.png",
       "scale" : "2x"
     },
-    {
-      "size" : "76x76",
-      "idiom" : "ipad",
-      "filename" : "Icon-76.png",
-      "scale" : "1x"
-    },
     {
       "size" : "76x76",
       "idiom" : "ipad",